I had a really bad reaction to the AZ Covid jab and one of the things which helped me with even being able to stand was massaging my legs and using the hot and cold settings on the shower to encourage blood to flow and the swelling to reduce. The pain was still memorable but it reduced quickly - I was showering up to 4 times a day though, and spending about ten minutes each time. I know the position of arteries and veins, so can work out where down and up should be happening.
I decided that my feet seemed bruised, so I did not walk about barefoot but added layers of soft innersoles to some sandals with velcro adjustments, so as not to put pressure on my feet. I then cut out innersole shapes from some lambskin pieces and that really reduced the pain and over a couple of days increased my ability to move around.
Whenever my feet feel even the least bit different these days I go back to the same remedies, as I have had a couple of run ins with what the GPs decided was cellulitis, equally painful.
These days I am ultra cautious, I wash my feet and rub an antiseptic cream on my toes before and after cutting my nails - but my grandmother's amputations began with a pair of nail clippers, according to my father's recollections, so that helps no end with the diet and the prevention.