Chance of pregnancy?

Well, I'm honestly not sure how long my cycle or any of that is. I guess my question is more of, what do you think the chances of me being pregnant are if I took the pills as directed and initially 2 hours after the instance? Like, does ovulation play a factor in the probability or not? Things like that. I'm extremely worried and I don't want to be pregnant. Also, it has been 10 days now since the incident. I haven't experienced any bleeding or abnormal symptoms. Should I be worried? I know I sound a bit repetitive. I'm just scared out of my mind. I can't even sleep anymore. It'd be easier knowing what the odds are and what I'm up against than wondering.