Questions about taking Ecstacy PLEASE HELP (:?

Okay so i'm 95lbs and 5ft and I have no idea how much to take..I'm going to be in a comfortable surrounding with my bf and bestfriends. ANDDDD..will it show up on a THC drug test? How long does it take to leave your system? WHAT DOES IT FEEL LIKE? Does it give your stomach a weird feeling? This ex is clean cut btw :D IS DRINKING ALCOHOL WIITH IT BAD