my first time on IF2 i was completely tired ...and so darn thirsty i couldnt get enough water..i had non stop headaches round the clock ..so bad i would have to take white willow bark on a continous basis to get rid of the headache....but the second time i did the bowel detox all was fine...no headaches no thirsty...i am now on my 3rd bowel detox...all is fine...i think your just not used to it...maybe 2 weeks is not long enough to be on the IF1 first for you