Since I also have OCD, I can identify what you are doing right now and it is looking for reassurance. Just as a purely statement of fact, several of my friends have admitted to masturbating somewhere besides the privacy of their own room at some point in their life. I myself did it in class once in 8th grade. I'm not exactly proud of it but when you are young your hormones are going crazy and you can't help it. Everyone has stuff like that they've done when they were younger and if they say they haven't they are lying to you. If you admitted this to your boyfriend he would likely admit to something similar to what you've done. You are probably even in the same boat as him if he admitted all the things he did going through puberty! Would you judge him as harshly as you are yourself if he admitted to all the things he's done (believe me he likely has some). Now aside from that, 100% of what you are going through is related to your OCD. I don't believe you have been suppressing the incidents all along, I think you were just ignoring them because they were useless information and someone not suffering from OCD wouldn't give it a second thought. However, your OCD has latched on to this (hence your realization) and you are looking for reassurance that everything will be okay. It is extremely hard (I know I have OCD), but I think the best thing you can do right now is say "maybe I did commit a crime , maybe I didn't. Maybe I am a sicko maybe I am not." Try to not answer the question your OCD is forcing you to seek because there is no answer that will ever satisfy you. Believe me, you will never ever find an answer to anything to do with the scenario you are in because it is based purely on OCD. I've had similar situations with my OCD before and the absolute only way to beat it is to ignore it and cease all searching for an answer. I have suffered too from morality based OCD. In the end you have to accept the fact that you will never live an unmarked life. Every person on the planet has done something morally or legally wrong at some point in the past or future. It's part of the human condition.
Hope this helps a bit.