bleeding during sex?

i’m 18 years old and i recently lost my virginity (3 weeks ago). within the past 3 weeks, i have had sex three times. the first time went smoothly, with some slight pain. but the second time (3 days ago), my partner and i engaged in foreplay (fingering, kissing). when he was about to go in, he noticed i was bleeding! i didn’t understand why and i was so embarrassed (luckily, he didn’t mind too much. i cleaned up, made sure i wasn’t still bleeding and we continued.)

my question is, is this normal? i finished my period 2 days prior to having sex again, so i highly doubt i got my period. do you think he might have been fingering me a little aggressively?