I had the same happening I brought it up with my PA on Tuesday, she said to limit your sodium and increase your water, also avoid caffeine and such, some lemon water will help. Since I've done those things I haven't had any swelling.
It's mostly water retention. Once baby is born bet you will be peeing like a race horse for the first 24 hours. And it will most likely be bladder function as normal (before you got preggers). That's what has happened to me with both pregnancies and the swelling is happening with #3.
Hope this helps out. :-)
This is my third pregnancy & have had swelling with each one. My first one it started at 12 weeks, second wad the last month, this one started around 6 months. It hasn't never meant anything bad, just water retention.