How long before I will achieve a 6 pack?!

I am a 14 year old male, I am about 5'2, and about 91 pounds. I know im small so don't tell me I am because I know.

Anyway, I have been doing mixed martial arts for about 15 months, and it has done wonders for my body. My biceps, triceps and shoulders are all very big and shaped, my pecs are getting quite a lot of shape and my abs are starting to get an outline.

Im not quite at the 6-pack level but as I said the outline is showing (unless I am in the position to do sit ups/crunches, then you can see the 6 different abs). I do crunches/push ups most nights, I do about 55 push ups a night (I go down for 10, rest for 20 seconds, 9 then rest 20, same until I get to 5, after that I rest for 10 seconds in between) and I do crunches until I start feeling the burn (I don't count how many crunches I do). I do about 2 or 3 lots every night.

When I was at the pool with my school, people were complementing me on them. It felt strange because I have always been the really skinny kid. They were telling me how I nearly had a 6 pack and stuff. Anyway, having a great body isn't my number 1 priority. Becoming as good as I can at my martial arts is. The body is just a bonus, but one that I would LOVE to have. Not only will exercising tone my body, but will help my core strength.

So, my question is, how many crunches and pushups should I do a night, and how long until a great shape will break through?

Also, what should I eat and drink? I have a low body fat level already, so I don't need to lose weight, if anything I may need to put some on.

Thanks so much everyone!