Sexual abuse? Or am I overthinking it?

So. I’m not really sure what this is considered, or even if it could be considered anything. Either way it still really bothers me.

When I was 15 I had my first real boyfriend. He was 18. About a year into our relationship I lost my virginity. Every time we would have sex I would end up telling him to stop after we had already started. Most of the time he wouldn’t and if he did he would guilt trip me because he didn’t get to finish, so I would end up letting him again even though I didn’t want it... sometimes I would even cry and he still wouldn’t stop. He would force me and guilt trip me into giving him oral also.

Now I’m 20 and in a relationship with the most wonderful man and have been for 3 years. He is the only person who knows about this. Sometimes when we have sex I start to have “flashbacks” or the same evasive instincts as I use to have. And when I do he is really understanding and stops and just holds me. I’ve also been having very vivid nightmares about the whole thing lately and I have no clue why...

I don’t know if all that can even be considered anything but is this normal what I’m experiencing now....?