Can't let go of past

I have been dealing with different subtypes of OCD off and on for over 6 or 7 years now and one of the most debilitating has been the Health OCD and POCD. I've been to to a therapist before and discussed everything with him and I found that I wasn't some mosnter despite everything I went through. But every now and again I get the compulsive mindset to check through my history to see if anything would confirm or deny me being a pedophile. One thing that keeps coming up but I have had multiple people say it didn't matter or I was thinking too much about it was the fact that out of the multiple different videos of pornography I've watched throughout my life there have been 99% normal or what anyone would call normal porn both consisting of guy and girl, girl and girl, or animated/hentai at times. Sorry this is weird to talk about but everyone watches it so I am not saying anything that people haven't heard of. But what I am hung up on is there has been less than 1% I've watched that is mainly hentai that had girls of suspect age in it that I never sought out specifically or had an inate desire to see it just came up in the list of things I watched. Some towed the line and I stopped watching. But I was never really focused on that and I think to myself that maybe it was my negligence that condemned me. I've never in my life sought out child pornography ever but certain times I've watched hentai have come to forefront because of the compulsory nature to check for faults and cracks in my life to seek reassurance. I have told friends, family, internet forums, and my therapist and all didn't judge me or condem me at all. All of them said it was either normal or that I was being too hard on myself or that didn't define me or what I actually held most important morally. The fact that a licensed therapist heard all of this and didn't bat an eye should have given me the comfort I needed but the fact that I watched something even remotely close triggers the need to check and scan over my life repeatedly for signs or evidence. I have had all the behaviors since this started 7 years ago. Avoidance, body checking, mental rumination, guilt and shame over past, reassurance seeking. If I see any children namely small girls I instantly am filled with dread and fear and anxiety. But since going and taking to a therapist it has lessened significantly. But this idea won't get out of my mind. I feel like I've made a mistake and my mind won't let me forgive myself and move on. Whenever I am watching regular pornography, there's a part of me that says "your only watching this to resist watching things with children". Then I start to panic and ruminate on what that meant and doubt if it was true even though deep down I know I don't want that. But OCD causes immense doubt and second guessing. I am taking a few namely harmless instances and making them out to be indications I'm a monster of society that needs to be isolated.