I keep ruminating over this. I think I lied to my boyfriend

I told my boyfriend when I was having a panic attack that I and seen one other man's penis two years ago (before I started dating him), but that "there was no penatration or seminal fluid involved." He was very angry that I told him this because at the time he was feeling depressed and he's right, it was insensitive. I told him this because, in my anxious fervor, I thought it really matters to him that his was the only dick I'd ever seen.

However, I did get seminal fluid on me during the encounter with the guy two years go and I feel terrible for saying something deceptive. How should I feel? I cant tell him about thia because with his depression an dmy anxiety our relationship is already a little strained but healing. Did I tell a horrible lie? Should I feel horrible? Please help.

I personally would just let it go and not say anything more about it. It's the past before you were with your b/f? Then he doesn't need to know.