Anytime my horses feet where sore I would soak them in hot water.
I gave her bite last night and breakfast today. Going to check on her soon. Apparently the previous Farrier didn't touch the frog.
I would be see a vet! But you could also use a standing bandage
May want to look at finding a different if she's lame from a farrier trim. They should be better after the trim before...
However, cold hosing should help.