You just gave us your own answer...you are drinking and that is what is coming out...all of the fluids that you are putting in...
But, if you find that the skin on the back of your hand is loose, your eyes look really sunken in, you have lost tons of weight since this has started (a pound or 2 is normal, 10 is not), if you are seeing stars when you stand up, have a headache that won't quit etc then please call your doctor...
It means that you are dehydrated and on a slope that maybe self-treatment is not sufficient to climb back up from.
You may need I.V. fluids to get enough into you...so start monitoring intake and output. Try to judge approximately how much you are drinking compared to how much is coming out...if the difference is really huge, call the doctor...or go to ER.
Sharon