I had this also, they sent me for a ultrasound to check for clotting as it was really bad, to the point I couldn't bend/flex at the ankle or scrunch/point my toes. But there was nothing to be seen & its just "normal" preg swelling. Its really humid here though so I think it was just my body going WOAH! its humid LOL. It settled down heaps but its still a problem for me & by days end my feet are really sore & the tops feel bruised to touch. Plus just yesterday I started getting a jutting pain up the back of that ankle that swells the worst. Typical though, I had my midwife appointment last friday when all was "well" now I don't see her again for 3 weeks. But if the pain gets worse when I am standing I will call up.