Hi Erin,
Hugz! dun worry! things will be ok! try sleeping on your side... and wake up at night to turn to another side before turning back to the left side.. will help if u have extra quilts/extra soft cushions supporting lower back also.. I get the same aches, but for me, i put extra thin mattress and i take my spare quilt, fold it up and use it to support my lower back.. it helps.. at night, i spend like 60% of my time on my left side and 30% of my time on my right side.... so far, it seems to work ok for me, since end week 27, my baby weighs 1.1kg.. I am conscious enough to wake up and slowly turn around in the night, cos i scared baby can't get her nutrients..
It must be working, cos every morning, even if i take a small glass of warm milk or wholemeal snack before i sleep, i wake up super hungry in the morning!