Help determine age of my Argentine black and white

[panzer05]

I just got my Argentine black and white tegu recently from http://www.floridaherps.com/ I did not specify a size so when i received it, it was 2 pounds. I cant tell if this is fully grown or not and what sex it is. I hope it gets bigger cause i wanted a huge lizard.

 

[Jacobhreptiles]

it looks like a young male by the head but not sure, but that is no where near full grown.