I had this issue when pregnant though it sounds that it did not get as bad as yours. I am sure you will get many other suggestions and they may or may not work but I wanted to add what worked best for me!
CHIROPRACTOR AND MASSAGE THERAPY!!!!!!!!! GOD'S GIFT TO PREGNANT WOMEN!!!!! It is safe during pregnancy. Just make sure the chiropractor/massage therapist knows you are pregnant at the time you make the first appointment (some are more comfortable treating pregnant women than others). While there, ask him/her to teach you stretching techniques you can do at home for the painful areas. The chiropractor/message therapist worked great but he/she is not available 24/7. The stretches they taught me were invaluable during pregnancy with my sciatic issues (and I actually still use some of them today for stretching before working out). Not only that, but the therapy relieved me so much that the night after the therapy (that evening), I would sleep VERY peacefully and wake feeling very refreshed, unlike the rest of the time. I could tell within minutes of leaving the appt that I was more relaxed in the muscle areas and pain was still there but not as sharp or intense. I became a massage and therapy junky when pregnant-LOL!
After a visit to the chiro/massage therapist or stretching out a pain on my own, a warm shower (i liked the steam) worked really good to soothe and calm me for sleep. At other times before bed, when I had to, I resorted to benedryl or tylonol pm at bedtime to help me sleep. Lavender also works well for peacefull sleep. They worked to knock me out but I did not wake refreshed but some sleep was better than none. Benedryl and tylonol pm are safe during pregnancy. If you use lavendar oils ON YOUR SKIN, make sure they are pure oils. If you are not sure, just use them as "sniffers" in the bedroom or bath and do not directly put on your skin (as if they do have any toxins in them, they will be absorbed through the skin but if they are pure, they are 100% fine to be absorbed)!
Some pregnant mommas I know swore to the pregnancy tummy wedge to sleep with. I did the pillow between the knees and slept as much in the fetal position as possible to take the stress off my lower back. I also sat on a sitting wedge (made for pregnant women but you can get the same thing made for other back uses)at work and that also helped greatly (I work a desk job). I also liked a pillow wedged up against my back at night when sleeping for support from spinal twisting during sleep.
Hope some of these work for you!