I struggle on my left too. Sleeping on your back is bad in case the baby lays on some sort of artery which can make you feel faint and laying on your right means your baby can squash your liver... my answer to that? Its not hurting your baby itll be you feeling rubbish so sleep how you like! Get a good nights sleep :) ive started laying on my back partially sat up but bought a maternity pillow today to try and get comfortable. Xx
Sleep however you feel is comfortable. It's recommened but nothing bad will happen if you sleep on your right. I do both and my back (propped), and I find my back more comfortable than anything.