All of a sudden swelling

Aubrey • DS born May 21, 2018, surprise with #2 due Aug 2019

I’ll be 38 weeks tomorrow. I’ve been in battle with a headache since last Saturday, had blood work done to check for preeclampsia twice last week and everything was wonderful. My BP isn’t high either. All of a sudden yesterday my feet have swelled up and it’s not going down. I haven’t been on them very much at all, less than 6000 steps a day. Any ideas? I hate to call or run to L&D; for something that’s nothing and a just a normal pregnancy symptom. Help!