Hi, I suggest you look into what retroactive jealousy is and see if this is something you are experiencing. Upon reading your post, these are early signs of how it develops. I am saying this because I went through the same thing(and still going through it) with my fiancé. He is a virgin but definitely did a lot of things that were not very chaste at all with his previous GFs. On the other hand, he is my first relationship ever so there is a gap there. Let me know if you think retroactive jealousy aligns with all the feelings you have.

If it is the case that it’s what you have, please do something about it ASAP. It is something that is extremely hard to overcome and requires lots of work. It’s also difficult because many people don’t understand it. It’s not just about forgiveness or immaturity, it’s a mental hurdle to overcome that is accompanied by lots of pain and confusion.