It was then the radio crackled with more bad news: Five men were pinned down inside a Humvee. Among them were Romesha's close friends in the platoon: Sgts. Justin Gallegos and Brad Larson.
They were taking heavy fire. They were running out of ammunition. They were unable to hold out much longer.
As the gunfire and mortars rained down on the Humvee, Romesha spotted several areas where militants were firing from.
His plan, Romesha radioed to Gallegos, was that he and another soldier would lay down cover fire so the five could escape the Humvee.
Romesha and Spec. Justin Gregory scrambled atop a generator and opened fire, focusing on the Taliban fighters firing at the Humvee.
By doing that, Romesha made a mistake, he would later say.
The staff sergeant had always taught his troops not to fixate on a target. "Keep your head on a swivel," looking to the left and right, he told them.
As Romesha was focused on trying to help the men in the Humvee, the "enemy had snuck up on my right side and fired an RPG right at the generator I was on."
The RPG knocked Romesha onto Gregory, who was wounded by shrapnel.
They were dangerously low on ammunition. The staff sergeant picked up the last belt of ammunition and started to fire.
"Everything was a target at that point. There was movement everywhere. The muzzle flashes were everywhere. You just couldn't pick them out fast enough," Romesha said.
"I tried to hold it as long as I could, but when you're the only machine gun talking on the COP at that point, you start drawing quite a bit of attention."
Out of ammunition and under fire from all sides, Romesha failed in his mission to help Gallegos, Larson and the others.
"I called Gallegos and told him I was sorry," he said recently, pausing as he was overwhelmed by the memory.
"I just told him I was sorry. ... I just couldn't hold it anymore. Ran out of ammo and that position was compromised. I just couldn't put enough effective fire down for them."
Chaos was continuing elsewhere on the base. The roughly 20 Afghan soldiers based with Bravo Troop had fled or were hiding, leaving just the American troops to try to battle back.
Maybe it was the adrenaline. Or maybe it was total concentration on trying to save the men in the Humvee.
Whatever it was, Romesha never felt the injury caused by the RPG that had minutes earlier knocked him into Gregory.
"Dude, you have a hole in your arm," Rasmussen said as Romesha arrived back at the barracks to regroup his soldiers.
As Rasmussen bandaged the staff sergeant's arm, something much more serious, much more dangerous was playing out: Taliban militants had breached the base.
The message went out on the radio: ENEMY IN THE WIRE.
Inside the barracks, Romesha was assessing who was still alive, who of the wounded could fight and how much ammunition was left.
Sgt. Joshua Hardt approached Romesha with an idea: He would take two soldiers, grab a Humvee outfitted with a .50-caliber machine gun and make a run to try to save the five men pinned down.