I did MDMA yesterday after being clean for 6 years, I abused amphetamines/MDMA when I was around 18. I also am a very anxious person although I would not say it is a diagnosable disorder.
Anyways, I took 1, the redosed with 0.5 after a couple of hours or so. Overall it was a very nice experience, although perhaps not the full magic of the beginning, but still an extremely euphoric and enjoyable experience. That being said, during the comedown I did feel quite anxious and had to smoke weed to deal with that. It also made me want to have some alcohol to calm down, which I didn't because I don't like the idea of mixing it.
I can understand the fear of relapse. I had bought 3 pills...after my roll I threw the other 1.5 in the garbage to prove to myself that I didn't need to abuse this substance like I used to. The safest decision is probably to never try it again, but if you do try it just be safe, test if you can, low dose, and supplement with antioxidants/5-HTP