AR-15 experience was not traumatic at all.
Remember the journalist who said the "terrifying" AR-15 "felt like a bazooka and sounded like a cannon?"
He got "temporary PTSD" from the experience.
Well, worry not -- I survived my first AR-15 experience without trauma. Having put a few hundred rounds through it, I can report it was a blast.
I'm no gun nut - my only prior rifle experience was a .22 bolt action rifle I got to shoot one time in the Boy Scouts. My only range experience in the last 10 years was taking some UK interns shooting five years ago. (I do regularly practice with my pistol at home using a laser training cartridge.)
I was a little intimidated at first because ammo is expensive, and I had no idea what I was doing. It took a while to zero in my sight because I stupidly forgot to screw it in after using my laser. After two hours I was able to consistently get within a few inches at 100 yards.
I liked shooting a rifle better than a pistol. Pistol shooting uses the whole body, but with the rifle, I just focus on the sight, breathing, and trigger pull. It's also a team activity because you can't see the target at 100-200 yards. A friend came with me, and we traded off shooting and calling out shots with a scope.