I have PTSD from a disabling industrial accident.

The sooner you get treatment, the better and easier it is to treat. With that said, since the Army didn't treat soldiers for PTSD on a regular basis *until the current wars* it's probably going to be a long haul for you.

The reactions you ended up with from that first shooting have had a domino effect, I think, and caused you to make other decisions based upon the poor reactions...and then more less than healthy decisions/reactions based upon those bad decisions... etc.

It's also probably taken a toll on you physically, as the cortisol runs rampant in our bodies with the fight or flight situations always being forefront in our minds.

Now with that said, psychological treatment with an expert in PTSD is what you need. If during that time you need medication to help calm the anxiety (PTSD is an anxiety disorder) or to help you find restorative sleep, then do so.

A good point about all this is that you won't necessarily have to pick through all the traumatic incidents in your life. Part of PTSD is that the brain chemicals dumped during the original trauma (especially) caused the memory of the shooting to not be filed away properly. The subsequent traumatic events likewise, weren't filed either. (I picture it like all those files are lying scattered all over the brain's/mind's floor.)
Once you begin to process the events that keep you on edge, the brain will have an "ah ha!" point and subsequently begin filing all like kind memories.

So there is hope for life without it being controlled by PTSD. At the present point there is no cure for PTSD, unfortunately.