you usually dream about something when you are thinking about it,most probably you got the dream because you must be thinking about it for a while.i don't think its weird to have this kind of dream..it okay..common!!
that means that you are not sexually satisfied... scintific tyerm sais that people who think of sx alot or dream of them then thet are not sexually satisfied & those who dont dream of it are satisfied
Because you have a desire for it maybe? Just a guess. Look it up like on dreammoods.com if you're that curious