SO Nervous

Hi ladies! In December I found out I was pregnant. I went to the ER due to cramps. (FTM here.) Well, doctor said everything was well, I was 5w6d. Heartbeat was 60. ( that scared me cause it was low, but she assured me it was normal since the baby just formed it's heartbeat.) And my levels were 8,115. Tomorrow I go for my 12 week scan and I am so scared. What if something goes wrong? Any other mamas have this???