Not necessarily. The number of HITs available just means there are x amount of unique HITs left in a batch. Depending on how the batch is set up, you might be able to do them all or you might only be able to do one. It varies quite a bit.
Also, if you have questions, you may get quicker responses if you ask in our Daily Work Thread. It's where we all kinda hang out and discuss HITs and other stuff, throughout the day. New threads are posted here, daily: DAILY WORK THREADS