I can relate to your traumatic experience though. Happened to me once or twice. But not on MDA/MDMA.
I was at school one day and I snorted an unknown/branded research chemical, a super bad stim with shitty cardiac side-effects and paranoia.
After about 40 minutes after the first line and 10 minutes after the second (I was stupid enough to take a second line) I noticed my heart rate go up really fast. I had just seen a documentary the night before about people dying because their hearts blowed up from speed and I immediately started freaking out. I left the classroom and went outside. I was spinning around in circles trying to calm myself down. My heart was beating probably at 180 BPM at this point. My fingers started getting numb, feeling like many small needles were coarsing through my veins, heart was palpitating, my mouth was so dry that I couldn't talk properly. I ran out and went to find a pharmacy.. I was delirious walking down unknown streets and asking everybody if they knew a pharmacy - this was a very traumatic experience for me because of the sheer panic, I was 100% CONVINCED that I overdosed and if I couldn't get any help in 5 or so minutes my heart would blow up and I'd die on the street. An indescribable feeling of impending doom - probably what death-row inmates feel just before they get zapped in the electric chair.
I got to the pharmacy, a doctor was also there, she took my pulse (180) and called the ER. She gave me beta-blockers and I calmed down.
I was nowhere near an OD, probably.. but the substance was shit, it made me feel like I was dying.
So whenever I would go up some stairs after that, or take a jog, and my heart rate would go up I would be constantly checking my pulse and having paranoid feelings creep up on me. These went away though but I still had severe panic attacks while high on weed. As soon as my heart rate increased I'd be convinced the weed was laced with some crappy research chemical and this would kill me - caused me to panic even more - caused my heart to rise up more - caused more panic - cause more heart rate... it's a vicious circle.
Only now, 5 months after this incident have I been able to stop my panick attacks.
I did some really intense soul-searching and I got to the root of my anxiety/paranoia. Now whenever I smoke I can mentally block any paranoid/bad thoughts seconds after they pop-up in my head and successfully avoid a bad trip.
My advice to you is, try and lay off weed for 2-3 weeks or so. Do not take benzos (they cause rebound anxiety). Try and get sleep, have fun. And while you're sober try to find the root of your anxiety/paranoia and keep telling yourself that you have no reason to EVER be paranoid about these things. Do this every single day - try and meditate and re-live the experience with MDA, but this time, try and keep calm and assure yourself that you have no reason to freak out. Your brain works that way, it associates certain emotional states with trigger elements. My trigger was my heart rate going up, and my emotional state was sheer panic and feeling impending death, I had no control over it at first, no matter how hard I tried, I'd freak out while smoking weed because of the traumatic event where I ended up in hospital after my stimulant use. When I started trying to re-live the traumatic experience over and over again in my mind I would get super anxious and scared just by thinking of it. The more I thought about it though, the less traumatic it seemed. So by reflecting your past experiences, you can learn to accept them and move on - so your brain will not associate the trigger with the emotional state anymore. Now I don't get paranoid about my heart rate blowing up anymore
If you face your problems head-on, rather than run away, you will recover. Hope this helped.