well you are smart by not taking more beans. thats how you will poison yourself. you wont roll harder by taking more. also, water is good but don't go overboard. that is equally bad in large amounts...
someone said it though... you have to wait a week or so so your tolerance level has gone down. then try rolling again. also, if you have the chance, I had a lot of fun mixing acid and xtc a few years back... (candy-flipping, trolling, etc.)
I assume If you like xtc then you have tried acid before...
btw, you have no idea of knowing what is in those beans... so potency is usually give or take, along with safety lol. so be careful...