I have foot problems too.......too many years of carrying far too many pounds and having sensitive feet in the first place, I had issues even before I started nursing. I've since developed plantar fasciitis, fallen arches, hammertoes AND arthritis. So my advice to you is, you need to see a podiatrist, and SOON! Your feet will only get worse as your nursing career---and your age---progress.......trust me, you want to take good care of those tootsies, and a good podiatrist will assess your needs and figure out not only the right kind of shoes, but the right foot and ankle support. You will probably need custom orthotic shoe inserts, which can be very expensive, but they last a lifetime, and if you have insurance, it may help with some of the cost.
Some of the things you can do in the meantime are investing in a good pair of support hose, getting foot massages on a regular basis, even buying a commercial foot soaker with heat and bubbles......you can also add some salts or special oils to the water, which is very soothing and leaves your feet feeling pampered and refreshed.
Another thing I do once in a while is to slather Bag Balm all over my feet, put on a pair of thick socks right out of the dryer, and sleep in them all night long.........the next morning my feet feel fabulous, and I'm ready to tackle another 8 hours of running!
Best of luck to you.