For months I had poor, poor concentration and I would hear music in my head all the time. Now, who knows how it affected me later in life with depression, concentration, memory. MDMA is not benign. Stick with pot- it's about the safest drug out there next to aspirin. Even now I'll pick something up and forgot why, or forgot why I walked into a room. But I guess this does happen to everyone. I just know I'm not the same. I've probably done it 40 times.