Originally Posted by alan11

Sounds like what you are just doing would be considered an international transfer at Haneda.
Probably fine, as long as you are ticketed and checked in for the departing flight, and if not doing so in advance, check-in can usually be done at the int'l transfer desk within the terminal prior to going through immigration. However at Japanese airports you will still need to go through a security check (not immigration) with any int'l transfer.