Nope! But you do have to be in a very quiet area to hear your baby. It can pick up other noises and make it harder to hear your baby. Its very easy to hear the hiccups and movements, but my baby was a mover and it was a little hard at times to catch his heart beats. Just so you you know :)
oh well I'm sure you will be okay dear. 13 weeks is like the dead line for miscarriages. Your almost there, so no worries girly :) I have had 4 miscarriages, all before 13 weeks.