Oh, Rae - so sorry you are in pain! I know this pain; I worked retail for a while. I am with those who say that standing all day is 100% different than walking all day; I have also waited tables and it was nowhere near as tough on my feet as the standing job.
In addition to the suggestions you've already received (comfortable, supportive footwear for work, elevating your feet, hydrating, watching your salt intake at first, etc.) I would also try to sneak in exercise breaks whenever and wherever you can. Walk, squat, do anything to MOVE; you need to ensure your circulation is working.
Do not sell your lovely footwear. My solution was to wear a very low heel (but not an absolute flat, which does not give me enough arch support) while at work, to alternate shoes (not the same pair every day), and to wear my other shoes in my off-duty hours.