If the iPhone is telling you that you can try again after a timeout, there is still a chance to enter the right passcode.
If the iPhone is offering you an option to get in using your previous passcode, because you changed the passcode within the last 72 hours, you could try to get in that way.
If it is saying that it is unavailable, and is not showing you either of these things, there is no way to get in without erasing the phone and losing all data that exists only on the phone. (Depending on how the phone was set up, it might have already wiped itself the instant that you made the last incorrect guess. Either way, the bottom line is that any data that exists only on the phone is lost – and that neither we nor Apple can help you get it back.)