It will eventually get so bad you won't be able to eat.
No food = bad things to come. Infections can be particularly nasty (and lethal) if it isn't taken care of.
Car or nail next. I'd personally go nail because pain is pain and it wears on you mentally too after awhile. Use a cane (if need be) for the feet/nail probs till you can remedy it. Canes are kewl