AITA? I told my girlfriend a lie when we started talking and now it’s spiralled into so much more.

Ok so basically when my girlfriend and I started talking I wasn’t looking for anything serious. At the time I had a problem where I would tell a lot of small lies (a problem which I have since fixed). Basically I forget how it had started but while we were talking we started talking about virginity and I had mentioned that I had lost mine already to my first girlfriend (which I hadn’t) and we left it at that. Around 8 months ago we were having some really deep conversation about how she had a terrible experience with with her ex trying to do some bad things to her. And my dumbass trying to be all understanding and trying to relate to her problem without thinking made up a story about how I had lost my virginity to my grade 8 girlfriend but I only did it because she wouldn’t stop nagging me about it. (That nagging part about her begging me to have sex with her is true but I never did it at the time because I really wasn’t comfortable with it) but I ended up telling a lie that I did do it and that I really didn’t like it because I was uncomfortable with it and more details like that. This lie has been eating away at me for so long. I’ve made sure to fix my issue of lying and all the small lies I’ve told her I have already come clean about, but I just feel so shitty about this one and wanted to get it off my chest