Not necessarily.
If it doesn't have tibial hooks or bulbs, that only means it's not a
mature male. It could still very well be an immature male as well as a female. If you happen to catch it up on the glass, take a close photo with the macro on of the ventral side of the abdomen, with a clear view of the area between the first pair of book lungs,
like this. I know my way around a furrow and can probably tell you the sex

.
As for how old it is, there is no way to know for sure. As I said in a previous post, growth rate varies greatly depending on how warm it was kept, how often it's been fed, and what sex it is. A tarantula at that size could be anywhere from a 2 - 15 years old!