Bleeding second trimester?

Pia
Is it normal to bleed during this time period? I'm 13 weeks and 4 days and out of no where I started bleeding. Like I started my period. I tried to call my doctor but he wouldn't answer the phone. I'm not even going to the ER and I'm worried about my baby. My mom is telling me not to worry but I'm kinda freaking out. I started spotting, now I'm not bleeding anymore. Is that common? I wasn't cramping or anything. I was just started bleeding and my stomach felt weird afterwards. I'm feeling kinda weak so I'm relaxing in bed.