Stomach muscles

I just have a question for all of you who have already given birth. I just had my twin boys vaginally two days ago and I am doing surprisingly well. No tearing or burning when I pee. Not too much bleeding. My biggest concern is my stomach. It feels really loose and like the muscles are very weak. Is there anything I can do to help this? My stomach feels like a water balloon and it is tender. I'm a little bit afraid to touch it or use it. Any advice or suggestions?