@Kate815 Hello Kate, this is the community center, so none of the hosts here can give you specific information on your account. You may want to give Airbnb a call or message them on Twitter @airbnbhelp.
I'm not sure what happened with your calendar: if guests cancel, dates should be available immediately, as soon as the cancellation takes place. Are you sure that the guest actually cancelled, and didn't send you a request to cancel? If they sent you a request to cancel and you accepted (or if you didn't accept it yet), the dates would be blocked on your calendar. Best to call Airbnb to get it sorted out.