UPDATE
I called the doctor this morning and they were all booked up for appointments, the nurse told me to come in anyway and they'd listen to the heartbeat of the baby. So...the hubby and I went over there and she checked me out, the heartbeat was 154 and strong. Only problem was the baby kept kicking and moving, she had a hard time keeping up with it very long to get a good listen to the heartbeat. So (obviously) everything is going well, but this has certainly been a scare.
She advised me that the baby will get trace amounts of the medication in its system and that will cause it to stop being active, because the medication will do the same thing to the baby as it does to me. It is to be expected when I take a muscle relaxer that the baby may stay a little inactive for a while.
Thank you EVERYONE for your replies!!!! It has been not only helpful, but very supportive.