Prices will fluctuate often depending on availability. As the rooms get booked up, prices will tend to rise, or if lots of rooms free up, the prices could drop again.
One thing that happens sometimes is conventions will book up large blocks of room well ahead of time, lowering availability and subsequently increasing prices for the rooms that remain. But then in one fell swoop they can cancel them and put a ton back up for availability (at lower prices).
For these reasons, I NEVER book packages. Packages usually have a penalty if you want to change your reservation in some way. If you book room only, you can cancel for free up to a week before your arrival. Then as time goes on if you find that the rate is lowered, you can just cancel your existing booking and re-book at the lower rate.