Parakeet's foot discolored?

Hey, I've had this parakeet for 9+ years and lately I've noticed some weird things going on with it. Over the last week or so, it's had great difficulty jumping and climbing along the walls of its cage. It takes 5+ minutes for hit to reach its perch whereas before it would take a second or two. It's feet are normally pink but I've noticed one of them is discolored--a bluish grey. Its opposite leg (not foot) is also a bit grey. Is this indicative of some foot injury or is it just getting old? I'm really worried because I can't afford a vet and I'm afraid it might be in pain.