As long as you are not trying to sleep on your stomach, you should be fine. Your not smashing your baby. Its space is becoming more confined, since its grown alot. it will not move as often now that its head is down and in place in the birth canal. You can count the kicks to verify the babys active, just to ease your mind. You should be fine. You will probably become more uncomfortable as the days go by. Probably very uncomfortable right before its time to have the baby. Just remember, you baby is usually very protected when they are inside of you. Best Wishes. You'll be feeling better soon.
your baby is protected. if you feel too uncomfortable on your side at night, change sides. try supporting your belly with a pillow. in my last few weeks i felt the same