Unsure about what is going on

So I'll admit I didn't have a very good weekend as far as the diet and exercise went.  I haven't been to the gym since wednesday and I can't let that happen, but I am going to get back on my 5 day a week schedule.  However my body must be doing something very strange.  I ate bad over the weekend and by bad I mean an extra 1000 calories a day so maybe 2800-3200 but somehow from Wednesday when I was at 304 to today, it went up 8 lbs.  I don't know how that is possible, 8 lbs is 28000 calories, I could have understood a pound or even 3 but 8!  So today I'm going to flush with a lot of water and get some extra fiber as I feel like my body is retaining everything.  I think it will help I just hope it helps a lot.  In any case I'm not going to fall off the wagon because I am changing for life and maybe I just delayed how quickly I'll drop weight but it is still going to come off eventually.  I read about people who have cheat days all the time and I never do it, I have a cheap 2 days because friday and saturday were really my only bad days and this happens!! Guess I won't ever that happen again.