Answer:
the aren't really side effects i for one would know because ive inflated my stomach before you may get some pains in the abdomen but that's all they will go away quickly and no there are no dangers from belly inflation doctors use the method of inflation to help get better access to the body during operations so it's completely safe!
it is possible to overinflate yourself, but just don't push yourself too hard and you'll be fine
go as big as u possibly can and ull be fine if u go to small it can get stuck go until you feel like crying then it will go down but it wont if its to small and ull be stuck like that forever. also u can gt pregnant if ur a girl so be carefful!