99% Sure I Have OCD

I'm almost completely sure I have OCD, I fit the criteria perfectly and have tested positive on many OCD tests, including the one here at PsychCentral. However, my parents say that it's impossible for me to have OCD because I have a messy room. Any suggestions on how to get them to let me be medically tested/diagnosed/whatever?

That is so frustrating. You could try to explain to them that you've tested positive on many tests already, and that OCD isn't a cleaning disease. Maybe have them read some basic information about how OCD works.

I second what Stone said. I, like you, am also very sure I fit the diagnostic criteria. I don't exhibit the "neatness" type of symptoms. I'm messy and don't feel the need to wash my hands constantly (or any other stereotypical OCD symptoms). However, I have near-constant intrusive thoughts, some violent, some sexual. They heighten with stress and I have a hard time fighting them. For example (I know this sounds strange)...when I'm getting dressed for the day and picking out, say, a pair of underwear, my mind will have a thought like "pick this pair and your father will die" so I tend to pick a different pair. Some times I actually think these words, sometimes it's just a "bad feeling" I get when holding a particular pair, so I choose a pair that "feels" better.

Hope this helps, for what it's worth. Like I said, I haven't been officially diagnosed at this point but I've had these and similar symptoms for over a decade now, starting in my mid-teens.