Back pain 😧

Brittany • Mommy to one sweet girl, expecting another precious girl in September
My lower back has been killing me all day... not sciatica pain, or anything, just constant pressure. Changing positions doesn't help, either. It hurts when I sit, stand or lay down. Anyone know if you can use stem/TENS therapy on your back while pregnant? Im only 25 weeks today, it's too early for this level of discomfort!!