236 isn't the most healthy weight for someone who is 5'7. You may just want to make sure you aren't over doing the junk food and that you are active..being active and avoiding junk food will make you feel better anyways =]
If you are really worried then u should go talk to your doctor- don't just try something without talking to a doctor about it first. Try to eat healthy and find a way to excercise that you enjoy- and always remember that God made you just the way he wanted to and HE DOESN'T MAKE MISTAKES!!! Sorry didn't mean to start preaching at u there but I have to remind myself of that every day. Just know that the inside is what counts!