How old? It's really hard to say...it sort of sounds like a really bad ear infection; one could be throwing off her sense of balance, which would make her walk funny. Sniff around her ears for a really bad smell; if it reeks, you can be pretty sure that's it.
Take her to a vet as soon as you can; if you think it's expensive now, it only gets worse as they get sicker.
Take her to a vet as soon as you can; if you think it's expensive now, it only gets worse as they get sicker.