Hey guys, met a girl like 3 weeks before in college (she is in the same class like me and we are not dating)

We always went to class together but the last days i had some private family problems and felt like shit in college and i was really negative towards her. I ignored her a bit and she asked me if we should meet but i just said no. she is obviously a bit mad now about me and doenst really wanna see me anymore.

Im such a idiot and feel bad about it. What should i do or say to her?