When I had congested heart failure there was pitted peripheral edema and called pitted edema and when pressed at the angle there is an indentation. The most common systemic diseases associated with edema involve the heart, liver, and kidneys that causes retenton of fluids.
To add to what has be said with non-pitted edema the most common local conditions that cause edema are varicose veins and thrombophlebitis (inflammation of the veins) of the deep veins of the legs. There may be some leg pain with those conditions.
You should consult a doctor to rule out any medical condition associated wth body system. Thanks for saring and if you have any further questions or comments, you are welcome to respond,take care,
Ken
Flycaster has given you some great guidelines. I don't have heart "disease" but I do have arrhythmias. Oh well. I think the average person will have some swelling of their feet and ankles if they've been up and around all day. Surely you've heard people talk about their shoes feel tight because their feet are swollen by the end of the day. And our hands may puff up a bit too on a hot day. Very normal.
If you develop other symptoms as Flycaster mentioned, it wouldn't hurt to have a checkup and ask the doctor how your heart is doing. But at this stage, if you aren't sure your feet are swollen, then you probably don't have a problem. I've seen heart patients with swollen feet and ankles and there's no doubt at all about what's going on.
If you are retaining fluid from heart-related issues, I am sure that you would have other problems, like strange heart beats, breathlessness, and chest pain.
As a veteran of heart problems, I suggest you weigh yourself first thing in the morning after the usual nature call. If you have gained two pounds or more in two successive days, that's a clue you have heart issues.
congratulations for walking two miles a day, that will serve you well.