yea like others have said sometimes OCD does come with having intrusive or delusional thoughts. I also checked out your profile it says you have Sexual Masochism & Sadism Disorder. here in my location when someone has these problems its part of it to have sexualized thoughts and worries that may or may not be true (in other words intrusive or delusional thoughts)

my suggestion is talk with your treatment providers, they can tell you whether you were sexually abused as a child or if these sexualized thoughts are part of your mental disorders. your treatment providers can also help you track down your childhood records documents... (school, mental and physical health and police reports and such that will contain information as to whether you were an abused child or not, sexual abuse isnt just about sex, other tell tale symptoms\problems would have been documented by your teachers, doctors, other family members and what have you)

Im guessing since no one has told you that you were sexually abused as a child and your medical\mental health treatment providers havent addressed this when they obtained copies of your past medical and mental health records, you can probably rest easy that the odds of you being sexually abused is pretty slim, otherwise someone (family, doctors, teachers....) would have brought it up with you. its usually the first thing here in my location that gets addressed when someone gets diagnosed with a sexualized disorder.