Am I overthinking my girlfriend's past?

My girlfriend and I have been together for 7 months, and I truly love her. I see a future with her.
She has always been honest about her past. She had one 4-year relationship, and later she had a 3-month FWB situation that turned into about 6 months of dating, during which they lived together. She told me she only had sex within relationships, not with random people.

Today, she also told me that when she was single, she got drunk at a party and shared a quick peck kiss with a random stranger. She told me this herself and I didn't find out elsewhere.

Ever since, I've been struggling. Sometimes she jokingly says things like, "Don't teach the player" or "I'm a retired player," and now those jokes are making me overthink.

I keep feeling like maybe I'm just the "good guy" she settled down with after having all her experiences, instead of someone she genuinely desired.

The confusing part is that she's never compared me to anyone, has always treated me with love and respect, and I genuinely feel happiest when I'm with her.

Am I just dealing with retroactive jealousy, or are these feelings understandable? I'd really appreciate honest opinions from people who've been in a similar situation.

Thank you!