Try not to worry too much about how you sleep. I can't sleep on my left side for any long period of time due to complications of previous unrelated surgery so I spend most of my sleeping time on my right side. I have one beautiful son and now a precious daughter on the way and have had no problems. I don't sleep on my back anymore as it makes me breathless but the right v's left thing is not an absolute rule. The left side is supposed to be better for positioning the baby for birth but I do pelvic rocking and tilts on all fours throughout the day to try and get my bub into a good position and so far she is head down so all is well!

Good luck, you'll be meeting your little miracle in no time and the worry and anxiety will all just dissolve.