I can mostly only sit on my gymnastics ball
Look into a cozy bump pillow ! It’s so nice 🫶 also all fours or puppy pose helps.
I second the all fours! Child pose and cat / cow pose have saved me. I find relief doing kegels while tightening my lower abs hold for 3-5 seconds then let go. Do that several times while arching or curving my back in and out relieves tail bone, lower back, and pelvic floor pain. I also visit a prenatal chiropractor they unlock that low back. I go 2x a week to keep everything good
Same boat!! Using warm compress.