Hello Friendinneed: It appears you're a 3 year member.
But this is your first post. So... welcome to active participation here on PC.
I'm sorry you are having the difficult, confusing experiences you are having.
Unfortunately I can't be of help. Hopefully there will be other members, here on PC, who will have some thoughts they can share.
You didn't mention whether or not you're in treatment for your PTSD. Hopefully you are. That really is the best way to figure out what is going on with you & what you can do about it.
Here are links to 4 articles, from PsychCentral's archives, 2 on the subject of PTSD & 2 on flashbacks:
Posttraumatic Stress Disorder (PTSD)
Understanding the Effects of Trauma: Post-traumatic Stress Disorder (PTSD)
Why Do Flashbacks Happen? | After Trauma
Coping with Flashbacks
I hope you've found being a member here on PC to be of benefit & that we'll see more of you in the forums.