once again in horrible pain and would rather not take pills

Hi everyone, thanks for taking the time to read this. I am a 21 yr old who was recently diagnosed with endo (may 12, 2012). My question is how long does it typically take for endo to come back because I am once again in horrible pain. Also, I have been drinking a ton of water, and for some reason that seems to make it work. I drank a regular size water bottle and I have gone to the bathroom at least 10 times since I figured drinking that a few hours ago. It doesn't burn or anything when I urinate, it is just frequent and it seems to coincide with the pain. However, I did have a urologist look for interstitial cystitis and he saw no evidence of it, and said the bladder looks great. So, is it possible for endo to come back not even three weeks post surgery, and if so what are my options? I am only 21 and wish to have kids in the future. Also I am an avid fitness guru and I would rather not take a pill or shot that I going to make me gain a bunch of weight. Any insight or referrals would be appreciated. Thanks