I'm so sorry. You're too young to suffer so much. I just watched Kennnedy's home movies on the History channel and he was a very sick young man with colitis, Addison's and lumbar spine so bad he got a metal plate and almost died. He suffered so much and still became president. His story may help you. Hang in there.
Or herpies viruses? HHV6 and CMV cause colitis and all kinds of problems.
I've been diagnosed wrong many MANY times. Keep searching and hang on to your colon as long as you can! Have you talked to HV in "The Truth in Medicine" forum on curezone? He'll probably tell you to try ozone because it cures this stuff.
Email me if you like. I'm suffering with this stuff too and still searching for a doctor who knows something!