Back pain at 19+3

I started having severe lower back pain this morning and can't seem to get comfortable.  Is this normal around this time?  Changing positions doesn't help, I'm so miserable!  I called the doctor and she's not concerned because I'm not spotting.  Are there any recommendations to help?  I've tried the heating pad and Tylenol and it's not helping.  It feels like my low back is being gripped in a vice. 😣