Could it be a medication issue? I was having a lot of swelling, mainly in my left foot. My doctor switched my blood pressure meds from Norvasc to Avapro and within a few days, the swelling has gone. I've been on it for almost a month, and it's been great. I actually have ankles again!
I think we get so caught up in our sewing we forget to take breaks. The chair puts a lot of pressure on the backs of our legs. Even cushioned chairs cause pressure. Get in the habit of getting up and walking around a little. I hope you get a good report from the doctor.