Gym

I went to the gym again today and decided that I can't do all of the exercises that the personal trainer set out for me. I am just too uncoordinated, lack balance and far too prone to embarrassment to do them unaccompanied. Unfortunately these exercise are the ones that work on my "core" or abs as anyone else would call it, which is an area that I really want to focus on. So, next time I am at the gym, I will have to ask one of the trainers for an alternative exercise that doesn't require coordination or balance, or cause embarrassment!
Oh, I very much doubt it is the exercise and probably just a natural swing in weight, but I weighed myself at the gym today and have lost about a quarter of a stone since yesterday. Is that normal?