First, I'll remind you that individual results vary, so ultimately the only way you'll know for sure is self trial.
1) water gain is often 3-5 pounds. This is intracellular water retention, the water is stored in the muscle cells. Bloating may occur in the gut, but not often in the face.
2)loading is not required, but may get you results faster. I've seen a recommended daily dose as low as three and up to ten grams. I go with five (at 200 pounds). Of course, the bigger you are, the more you want.
3)Yes and no. The muscle gained while 'on' won't go away. Any muscle gained is real muscle, a gain that you would make with or without creatine. You may lose a few pounds of water weight, and lose a little fullness in your muscles. Strength should stay the same as far as maxes, but your reps may drop some.