Abnormal exam/ pap test

I had my first OB appointment this past Tuesday. Had an exam and pap and blood work. Nurse called me today and explained that there were abnormal cells from the pap test and will need to schedule an appointment to take a tissue sample of my cervix. I'm freaking out about this and dont know really what to think. This is my first pregnancy and I'm 12w along. Has anyone ever had abnormal cells or anything like this????