Back pain

So i have a spinal instability, which causes me to have pain in my back (mostly when laying down) normally. Ivwas told by my physical therapist that pregnancy of course would make it worse so i've got to do my best to help my back with support. I'm almost to my 7th week and my back hurt soooo bad last night i didn't get much sleep because of it and my back really hurts this morning. What remidies do any of you ladies use to relieve back pain?