Try getting a body pillow and laying on it or placing ppls under you. This is my third pregnancy and I've had a hard time staying on my left side also. Bt baby is healthy and that's all that matters.
It’s fine to sleep however you’re most comfortable during pregnancy. It’s unlikely you'll be able to sleep comfortably on your stomach as your belly grows, but you can sleep face down for as long as it suits you.
The one position your caregiver is likely to warn you against, starting at mid-pregnancy, is lying flat on your back. That's because lying on your back allows your growing uterus to compress the large veins that run up the side of your spine and return blood from your legs to your heart. This can result in decreased blood flow and may cause dizziness, shortness of breath, or a fast heart rate.