Heh, that must kill you on an exam, having to fill in a box so perfectly...hopefully you can perfect your straight line technique.
I hear you about the parent thing. I think it's hard for a lot of us to really remember what it's like to live under their yoke, unless they were particularly abusive or something. But for parents that are just a bit of a hassle, they can be all right people but a huge pain to deal with when you're living under their roof. That will change quickly enough, though.
There is lots of stuff on-line about OCD, including techinques to help deal with your rituals. Something to help you out in the meantime.
Oh yeah, after I'm done with this post, I'm going to have to make another one somewhere else. Why? Because I always keep my posts at an even number.