ladies I really need your advice please!

for the past week I've had such bad lower back pain that at times it's unbearable. the pain is so bad at night when I'm sleeping that I literally (no joke) can't turn to my side..and when I do, I'm literally saying ouch. even when I cough I can feel the pain and it feels like all the bones in my lower back were cracking. I have no idea what to do or say to my doctor because I've already been to the hospital so many times this pregnancy with issues.