Zie
since you are not in a situation to get professional help lets try this, give us the following
1. your height,
2.your inseam (standing barefoot, back to wall place a book about 1" thick comfortably against your crotch and then measure from floor to top of book)
3 your weight
4 arm length , with arm outstretched to your side measure from the intersection of your shoulder bone and arm (socket)to your knuckles
5 do you normaly ride with the handle bars above or below the seat? how many CM above or below?
6. On the bike that is too large m tell us what you like and don't like about it in relation to comfort
7. what is your past Cycling experince ?
Chances are one or more of us maybe be close enough to your physique size to offer you an idea what may fit.
Rick