Pairing an Apple Watch

Just got a new iPhone and am trying to pair it with my new phone. However, you have to have the email and password that you used when you originally set up the watch. I have the email but I've changed the password that was used originally and have no idea what it was. I've called Apple Support and they asked for the serial number from the watch but the watch will not change screens so I don't have access to that, either. Any suggestions?