Yeah, I guess I will be sending it back. The battery still holds a charge, and it's getting more time now when I pull the plug, but if that circuitry is shot, there's nothing I can do.

I will talk to the guy and tell him I want to return it for an exchange. It was from a company in the USA, and the battery was relatively cheap ($35.99 shipped) so shipping it back may be no more than $4 from USPS.