You'll probably lose roughly 3-5 pounds, mostly water weight. As far as your strength is concerned, you shouldn't lose much, if any, as long as you keep your diet in check. If you do decrease in your bench, it's going to be a mind thing, because you're expecting to lose strength, so you will. Try to get yourself to think that the strength increases you've experienced will stay for good now, even if you're not taking creatine any more. You should be fine, just think positive.