Back pain and “stretching” belly”

I’m 10w1d with my second pregnancy, but my first to make it anywhere near the second trimester…

I have been experiencing EXCRUCIATING back pain. I used to be a powerlifter and I have never felt the back pain I’m experiencing now. I’m also having the pretty bad “cramping” (my mom keeps telling me to stop calling it that lmao she wants me to call it “stretching”)

I have a heat pack and I work as an athletic trainer so I always have access to heat packs at work but I want more remedies bc I know giving myself heat for long periods of time isn’t necessarily advised. The pain is around each of my SI joints(mainly on my right) but it radiates to my sacrum at times. I try to pop it on my own but the pain doesn’t subside.