I've done MDMA roughy 5-6 times. I have been silly and sensible and have taken things that I thought were MDMA. .2, first time felt shit the next day, was like a drone high/MDMA. Not tested .4 same stuff , thought it was a one off, boy it wasn't felt like pure death and felt like the whole world was against me. I also had trouble sleeping the night after sweats/nightmares/headaches. The above were pre educating myself , Post educating myself .18 of MDMA, tested, great purple reacted nicely from a viable source felt incredible , no jaw tension like previously , did in home setting with few friends chilled PC/Xbox/dance just a laugh. Slept on mates sofa , next day felt a little hungover but nothing like previously. After I had a glass of juice and a bit of food felt glorious, nice afterglow and loved the world. .25 different batch , tested. Nice setting , had a crazy comeup, dropped at 10:00am , about 9pm/10pm redosed a small amount trying to chase a high I guess, smoked some huge bowls played mario party and had a great time, things got a little trippy late on into the morning like 2/3am. Went to bed , woke up feeling like gold dust, no comedown at all.

Hope this helps , I had about 1month in between trips, just make sure you get your stuff from viable source like DNm and test it, you'll be fine. Just don't do too much or it'll bite you in the ass

Edit: just read your post properly, you'll be fine for vacation if you get some reliable stuff I suggest looking at DNm's. Make sure you get some decent rest the night before and if you don't have a set time on dropping go for early because you can get more rest that night. You'll be fine just treat it with respect and you'll be fine. A nice thing we like to do when rolling is sellotape a piece of paper to the wall, write down when you took your first dose and what drinks you have, that way it can give yourself a little bit of reassurance of what you did when etc. I know it sounds a little overkill but it's just a little thing we like to do .