hibernation period

I had heard around week 2 some people go through a hibernation period were they don't lose any weight. I haven't lost a pound in over a week and I'm starting to really worry. Everything I drink/eat (still on liquid diet) is suger free and 0 fat or very low fat. I'm getting about 500-600 calories a day which most of it comes from my protein which is about 250 calories for about 65-70 grams of protein. I'm drinking plenty of water, short about 8 ounce but I'm working on it & I walk about 1/2 mile a day. How long did the hibernation period last for any of you??? Thus far I have only lost 19.5 pds. since surgery, which was the 29th.

I had my surgery on June 4.  I have lost 46 lbs now--July 26.  I seem to lose about a pound a day.  Even tho I'm into the 7th week, I am still doing soft stuff and will go in for the balloon stretch of my stomach opening in a couple of days.  I have trouble w/anything that is the least bit big (diced chicken, bean, etc) so they will fix that and I'll do real food.  I kinda thought I'd lose faster doing the liquid too, but i haven't.  I never had a hibernation period though--in fact you are the first I've heard mention it.  I do think the changes will vary from time to time.  If you are getting that few calories, you should do the dropping at a good rate.  I'm not complaining about a pound a day.  Just keep doing what you do.  and keep up the exercise.