I don't think it's necessary. You would actually probably be more comfortable at home because you will need to be up and walking around. For me, there wasn't a lot of pain but soreness. For some reason a lot of people have shoulder pain which is just gas from the anesthesia. Make sure you have the drops for gas relief and the post op meds and you will be fine.
Sounds normal. You just need a fill. Personally, I've always had a hard time eating bread and pizza. That's when I know it's time for a fill. I had the same problem with constipation too. My Dr told me to eat leafy veggies like spinach and drink merimucil. Warm prune or apple juice works too. 4lbs is nothing to worry about as it could be retained water or anything.