On Our First Night, My Girlfriend Had A Little Bit

on our first night, my girlfriend had a little bit bleeding. i thought that was it. that i already teared her hymen because of the blood and i thought it will not bleed again. but last night she had a bleeding again. i asked her maybe she's on her period just then, but she was sure that she already had her period for this month. it confuses and worries me alot because there was more blood last night than her first. is that normal? or i just didnt completely teared her hymen on the first night? please help.