Girlfriend lost her virginity to mutual friend

We started dating couple months ago. We're in 2nd year college. I never asked her about her past. Last month she told me she lost it in school. I know the guy through football. She went to an extremely posh school in Kochi ( not revealing in post). She says all her friends from school lost it by 12th only. I never knew this really happened. Ive never done it with anyone before her. I respect her choice but kinda jealous this guy i know took her virginity. She told me details of how it went down and it made me even more jealous. Is it normal to feel this way? Anyone ever been in my situation?