Swollen feet and ankles at 21/22 weeks? Experiences?

I'm now 22 weeks. For the past week my feet and ankles and a bit of my lower leg have been really swollen. They haven't returned to normal in the that time. I'm on my feet a lot during the day and it's been warm and humid, so that's probably what it is. Hearing about preeclampsia, I gave my doctor's office a call last week. They said to come in only if the swelling isn't improved when I wake up in the morning...which I think it does go down a bit by morning.

Anyone have swelling this early? Any preeclampsia stories?