Ankle swelling is a common pregnancy affliction. I had major feet and ankle swelling from 28wks with my first pregnancy. Generally the doctors will keep an eye on your bp, your blood sugar, and proteins in your urine. If all these are at normal levels then you are ok. The swelling got really bad and my hands started to swell from around 36wks, at this point my doc was keeping a very close eye on me but nothing came of it.

Sounds like you'll be carrying big in summer. I recommend putting your feet up as much as possible. Get some cool sandals, and put your feet in a cool foot spa whenever you can.