Pap test results: abnormal cells.. what does this mean?

so i had a pap test done about a month ago, and the doctor called when she got the results to tell me i needed to come in for a repeat pap test in 6 months from my last one because they found abnormal cells. i have no clue what this means, but its really worrying me. my mom and i both have the same doctor and she is going to see her this coming week, and im thinking about going with her to ask the doctor what it means. i just wondered if anyone has been through this or knows about it, because its really scaring me :(