RAF MILDENHALL, England -- "Corpsman up!" rang out like a shotgun in his ears.
The 7-ton truck he was riding in just crashed back down after being thrown 5 feet into the air after hitting an improvised explosive device while on convoy in eastern Afghanistan.
The smoke and dirt hadn't yet settled, and former Hospital Corpsman 2nd Class Shawn 'Doc' Dickens strained all his senses - desperately trying to find the 11 Marines and Soldier who accompanied him on the convoy.
"Hearing Marines scream 'corpsman up,' is the last thing a corpsman wants to hear because that means a Marine is hurt," said Marine Sgt. Dickens, who left the Navy to pursue a career in the Marine Corps after that Afghan deployment. "As I went from Marine to Marine and assessed the damage, I blanked out.
"It's not like I didn't know what to do, but more like I treated everyone - but don't really remember doing it," continued the former corpsman. "I can remember before, and have memory once everyone was fixed, but the center is kind of fuzzy."
Of the 13 men on the convoy, Sergeant Dickens was the only one not injured. Sitting next to the spare tire in the truck saved his life. He remembers seeing the tire later and it was literally riddled with shrapnel, he said.
After the attack, Sergeant Dickens triaged, then treated each and every fellow serviceman on that Afghan roadside, and can still recall the most-severely wounded Marine:
"Cpl. Aaron Grossman had taken shrapnel through the backs of his legs," recalled the former corpsman. "A large piece literally tore out his calf muscle, while another hit near a major artery. Had I not removed it, it could have shifted and would have cut his artery. He'd have bled out in a matter of minutes."
After saving the team members' lives, four were medically evacuated out of Afghanistan, treated at a stateside hospital, and except one, all eventually returned to their deployed unit.
Sergeant Dickens didn't see Corporal Grossman again until he returned home. But, what happened during post-deployment defines what Sergeant Dickens considers the most rewarding part of his job as a corpsman.
At their barracks on Camp Lejeune, N.C., while moving as fast as his crutches would allow, Corporal Grossman scurried up to Sergeant Dickens' mom, gave her a big hug and said, "Thank you for having the son you have. If he had not been there for me when I got hit, I probably wouldn't be able to hug my own mom anymore."
"Until that point, I just did my job and didn't think about what I was really doing," recalled Sergeant Dickens. "But when I heard that, I knew I was really making a difference."
The former corpsman hails from St. Augustine, Fla., and knew by his early teenage years that he'd eventually join the Navy. In fact, he was so eager to follow his rich Naval roots that at a mere 17 years old, his parents signed waivers allowing him to enlist.
His parents weren't surprised by his decision to join either. After all, Sergeant Dickens' father, grandfather and step-grandfather were all in the Navy.
His father was an anti-sub warfare operator, but spent most of his time as a Sea Air Rescue swimmer and later a SAR instructor. His grandfather was a corpsman attached to the Marine Corps during the Korean War, and his step-grandfather was stationed on a submarine, and was part of the Tonkin Gulf Incident during the Vietnam Conflict.
"I decided to become a corpsman because of the stories my grandfather used to tell me," said Sergeant Dickens. "I was a first-aid instructor in the Boy Scouts, and have always been able to handle blood and gore. I figured being a medic or a corpsman was my best option in life."
Eager to learn all that the Navy had to offer, Sergeant Dickens attended every bit of medical or Marine field training he could - the medical training he hoped would one day help him save a life, and the field training he hoped would help him blend in with the Marines he'd be attached to.
"Apparently that big red cross on your forehead turned out to be a bad idea in combat ... ask the guys from Vietnam," said Sergeant Dickens citing that these days the only way to tell the corpsman from a Marine is the fact that the corpsman has two backpacks instead of one.
Not only does a corpsman have to look like a Marine, he must act, think and function like one too. Life, limb and perhaps sanity depend on it, he said. If a Marine gets injured on the battlefield, the corpsman has to run through bullets to get to him, that's his only chance at survival.
Admitting that he's always been pretty good at being in the military - and that it's clearly in his blood, Sergeant Dickens said that perhaps the biggest annoyance he's had to endure was to attend Marine Corps Recruit Training.
"After serving with the Marines for almost six years - even in the combat I described - I still had to earn the title of a Marine," said Sergeant Dickens. "But, I'm glad I did it in the end."
Among fellow Marines, Sergeant Dickens is still considered 'Doc,' and continues to serve the Navy's medical corps by passing on his knowledge to his fellow Marines, stating: The more they know, the more they bring to the fight.
A corpsman is very likely to get injured or killed running into gunfire and explosions when everyone else takes cover. But sometimes it isn't the physical scars that bother a corpsman most, said Sergeant Dickens.
He recalled one particular mission when he had to sit helplessly on top of a mountain and listen over the radio as some of his Marines got into a fire fight, and were overrun by Taliban fighters.
"Three of my Marines were on a patrol [June 24, 2004], and came upon a group of 10 Taliban, who were putting IED's in the road to take out a convoy," said Sergeant Dickens. "[The Marines] engaged and, after about 10 minutes of heavy fighting, were overrun."
Two of the Marines, Lance Cpl. Juston Thacker and Pfc. Daniel McClenney, were wounded in that battle near Bari Khout, Afghanistan, and later died from their wounds before treatment could get to them. The other was flown to a trauma center and survived.
"My pain comes from listening to them over the radio as they were shot, and knowing that they didn't have a corpsman with them - knowing that they had no chance at survival," said Sergeant Dickens. "I still beat myself up over the fact that I wasn't there to save them.
"This pain was later compounded when I had to see their parents at the memorial service and knew that I could have saved their sons - had I been there," he continued. "Looking into a mother's eyes and telling her that you're sorry for her loss while in the back of your head you know she wouldn't have lost anything if you were there, is something I'll never wish on anyone."
That was perhaps the toughest day in Sergeant Dickens' life. It was then and there he decided to leave the Navy and join the Marines. Sergeant Dickens is currently assigned to the Marine Corps Recruit Depot Public Affairs, San Diego, Calif.
Though his scars are emotional ones, they are now forever manifested on his body in the form of a tattoo. The former corpsman said that all he has to do is look at his leg at any time and he's instantly reminded of Lance Corporal Thacker and Private First Class McClenney - and why he joined the Marines.
"There's an unparalleled brotherhood between corpsmen and Marines," said Sergeant Dickens. "This clearly comes from professional corpsmen who are dedicated to their brothers and flawless in the execution of what they must continue to do."