Please help me, I think I have OCD?

Your 16, everyone questions themselves in their teen years. Sounds like your straight to me. Reassure yourself of that if that's what you want. Also remind yourself that being gay is nothing to be ashamed of, even if you aren't gay, we don't want you to get all homophobic in the process of 'finding yourself'. You have hit the emotional roadblock that a lot of people do. Well done. Keep going. It'll be in the past soon. :)