You poor thing. You are much too young to have a problem like this.
I am not a doctor but I've been thru a lot. You either need anti depressants or something for OCD (obsessive compulsive disorder). Why not try St John's Wort, an herb for depression? 900mg a day. At bedtime, take 2 cranberry extract capsules.
I really and truly believe that it's all in your head and that you could benefit from medication. Find a lady doctor if that would help you. WE CAN MAKE our bodies do stuff by using our mind in the wrong way. It's the Mind Body connection. So you have to have something to take your mind off your bladder. Good Luck to You.