Liquorice: Would I be correct in guessing that you're female? Sorry if I missed that in the thread somewhere. If you're female, 'bulking up' is the last thing you have to worry about- most women have to do seriously psycho excercise for very extended periods of time before this happens because they only carry a tiny amount of testosterone compared to men. There's no way you can bulk up on muscle in two months. Come to think of it, there's no way most men can bulk up in two months.
Two months is a very short period of time to make changes to your body. From what I've seen, losing fat can start quite quickly, it's the changing muscle shape that takes a bit longer. Doesn't sound like you have much in the way of fat to lose, but if you did maybe that would make you look more toned in the areas you mention (no way to tell without photos )
Anyway, you are leaving this quite late- if you really want to make changes, you're going to have to start immediately and really stick to an intensive regime that incorporates sensible rest periods for muscle recovery, and diet.
With such a short time limit, getting a personal traininer in would really be a good idea. You should find one via referral rather than looking for one at a gym- the gym PTs that I've seen (at Fitness First) are not very good. There are several threads on here that recommend PTs.