maybe you pulled a muscle or something is wrong with your bones. I think you should take Advil first and if it is gone afterwards for at least a week then you have nothing to worry about. I do think it is fixable because it doesnot sound really weird. maybe you have sat weird like hunched over or played a sport too rough. you could go to a chiropractor or a doctor. and you can tell your parents if you want to. if not those people then tell a friend and see what they think.