Teen age gap in high school

In high school I was a 17.75-year-old senior, and this guy I met through my mutual junior friends was a sophomore, age 15.5. He and I talked a bit and hung out once, and made out in my car. He respected my boundaries and I respected his. all we did was make out like I kissed and allowed him to touch my boob, I never touched his private since I wasn’t comfortable doing that. He would brag about his body count and give me sex advice, since he knew I wasn’t experienced. We both didn’t like each other like that and never wanted to be in a relationship by both of us. I made out once as a dare, or to try to seem cool, having a hoe phase and I ghosted him afterward since it got weird, embarrassing, and he was rude to some women that I was uncomfortable. We haven’t seen each other in over 8 years, and I just found out now that we had a 2.4-year age gap (2 years, 4 months, 27 days). I feel sick. I know a 1–2 year age gap is generally fine, but I didn’t realize it was extra months beyond that. I never knew his birthday back then, since we never talked about it. I just knew he was a 15-year-old sophomore, not freshly 15. Right after high school, I became interested in older men and stayed friends with my senior friends, and wasn’t interested with high schoolers of any age during my first year of college. Finding out it was a few extra months makes me feel sick, cougar and a creep. I can’t change the past and the people that I told said 2 years isn’t bad but I didn’t know he was 2.4 years younger. I thought we were around 1.5-2 years apart.