It is a male, but I would doubt it is a GT. If it is, real small for a 2 year old, as well as the tail base, and head looking wrong. Colors and pattern are also not what would be common for a GT locality. Take a picture of the head straight down from the top. The snout makes me think there is a chance it at least has Isle E in it.
As for sexing, at around 80-100 grams, you can see it with the naked eye. With magnification, I have seen geckos as small as 7-10 grams sexed correctly.