My dogs leg just above her "ankle" is what looks like a small nail growing out of her leg.

Does anyone know what this is? it is very small as it started looking like a spot but now I can see what looks like a small nail.

Please help

Is it her dewclaw? How old is she? How long have you had her?

Sounds like a dew claw

If she had her dewclaws removed as a puppy & it was not completely removed, it's possible that it has grown back but will probably never be as large as it would have been had it not been removed (if you see what I mean :) )

That's why I wondered how old she was. :)

She is 8 and has her dew claws. It is much higher than that really.

It was like a blackhead and now you can see what looks like a small nail growing. It may not be a nail but that is what is kind of looks like.

I could get a photo if it would help.

Let a vet have a look, sounds like a carotene (sp) wart.  My dog had one grow on his tail a few years a go, we were told it is where a hair follicle gets the wrong message and starts growing like a nail.
It isn't a health risk and you have two options, either keep it clipped like other nails or have it burnt out, which we did under local anesthetic