Severe Weight Fluctuation (within a day)

So I recently bought one of those Wifi scales (trying to build some muscle, loose fat), and I noticed a HUGE difference in weight from morning to night. The first time I weighed myself, I was at 191 lbs, which was up significantly from my normal weight, but I guess I thought I had just gained weight (I did feel like I was getting bigger). The next morning, I tried the scale again, and it showed 165lbs. A 26 pound difference. I thought maybe there was an issue with the scale the night before, so I waited, and weighed myself again last night and it was at 191 lbs again. This morning, back down to 165lbs. How can someone gain/lose 25 lbs in one day. Should I see ask my doctor about this? I've had my ostomy for almost 2 years now, and never noticed anything like this before (although, I never really weighed myself this much).

we generally fluctuate from night to morning- I'll weigh about 7 lbs or so less in morning- also, are you weighing yourself the same (IE with no clothes on?) Clothes can add as much as 10-12 lbs- Don't forget about your shoes too- also, put don't the bowling ball when you weigh yourself at night- that might be throwing off the scale :)

Seriously though- if you are weighing yourself the same at night and morning and getting that much difference, I would see about borrowing someone else's scale for a few nights to see if you are still getting such a drastic change-