Early Ovulation? HELP!?

Question: I am currently on my first round of Provera & Clomid. I think I O'd on CD13. I had EWCM from CD9-13, and on CD14 I was dry immediately. We BD'd on CD13. It is now CD16 and today I am very tired. I got an almost +OPK on CD13, however I am not BBT or anything. I just want to know if it's possible to O that early, and if it could have worked. I am driving myself crazy with all these questions and I am having trouble sleeping at night because of it! Any suggestions/answers will help!