Real Estate Laws differ from state to state, so you should check with your state Board of Realtors to find out for sure. You can also call the Agent's broker and complain about her lack of attention. Depending on the state and/or local Real Estate Laws, the broker may be able to transfer the listing to another agent.
You can also check your sales contract to see if there are any penalties for "firing" your agent before the contract expires. Your sales contract may also list what needs to be done to "fire" your agent.
-Michael