I tlkd to my dr today about my swelling and he said that if its fairly normal and that its only uncomfortable to moms and not harmful to baby. He recomended laying on my left side to help with circulation and he said that as many hours as you walk/sit/stand is how many hrs you shoukd lay on your side.
I'm the same way, its been happening since I was 32ish weeks and now I'm 39. Just have to lower your salt, drink loads of water and lay with your feet elevated.