Under shoulderblade back pain

22 weeks pregnant and been experiencing intense upper back pain. It's like under my shoulder blades. Not lower back. Is anyone else experiencing this? Or has anyone? The past 2 weeks it's gotten progressively worse. Sleep doesn't help. Trying to have better posture on the couch doesn't help. I work about 34 hours a week as a dental assistant but I can't imagine it's this causing so much pain especially when I get 3 day weekends and it doesn't get better. Anyways looking for advice!