Any remedies or recommendations for back pain?

I have having excruciating back pain since I had my embryo transfer. It generally starts around night time and almost numbs my legs. I wake up few times during the night and every time I drink water or empty my bladder, the pain reduces little bit. Nurse said it’s due to excess gas the embryo is producing and suggested I take stool softener which isn’t helping at all. I took some gas x pills as well as other laxatives but nothing helped. Im trying out heating pad on the spot but it’s hardly working. Any one have any diy remedies, medications, or any suggestions to ease up the pain? it’s been over a week and I know the pain will get worse if I don’t do anything any time soon.