First off, and absolutely most importantly, excellent user name.
I was in the Air Force and though I did take fire during an air drop my PTSD is not related. I had friends (three now) who died during their service, but I was lucky. I was an Afghan (Pashto) linguist aboard the AC-130U, MC-130W (now AC-130W), U28, and M28. My PTSD comes from killing. Being in the Air Force, we don't kill one at a time, and I find that harder. You don't get to look in your enemies' eyes, and you don't get to feel as if they are targeting you and that you are defending yourself. You kill because they are hurting people you are there to protect, and you watch it in HD on imagery screens. I have directly caused the deaths of at least one thousand people, but no Americans ever died while I flew overhead. I was unique within my unit for that, and so I'll live with my ghosts knowing that I did what I could for them at the expense of others.
There is a noise that I can't stand and that does bother me, and that's crying children, but usually I can just leave before it gets to be too much. If I stay too long, I don't function anymore. It's not panic. It's a rushing sound in my head that reduces my vision into a point.
I used to drink to fall asleep because I would have panic attacks every night where it felt like my heart was traveling around an inch at a beat. I tried not to get drunk because I knew what I was doing was not a solution, but I'll be damned if booze isn't the best medicine sometimes.
I don't like crowds, and I don't have a lot of patience or compassion sometimes. I don't know what PTSD is for everyone, but that's what it is for me.
There is a very very unique thing about PTSD though. Imagine that deep within yourself is a fire. Fires can warm you when it's cold, they can cook your food, they can scare away the night, and they can burn your fucking house down and kill you. That fire is unlit within everyone until they need to light it. People talk about how cool and callous military professionals are, and how they function at times when others simply cannot. How the new guy gets killed instantly when the old guys just knew to lower their heads.
They can be robotic because they've lit that fire. They can act with instinct and not let thought get in the way. They can do this because one day their life had become so cold and terrifying that they needed to light that fire. They needed it to scare away something in the night so that they could live through it. PTSD is the fire still lit when you don't need it to burn any longer. Because when the fire was lit, it scared away other things too; things like compassion and patience. Coming back to the real world is called re-deployment. It's a brand new fight.