Zen V Plus not responding

I used an emergency charger, bought at an airport, left it attached to Zen on plane; player is now dead, will not charge or connect to PC. There is still a blue light when plugged in but it is different to before (flashes when plugged in then quick flash every 20 secs or so, recharging icon not there). Have I ruined player? Could battery be gone? Player was fine until I used the crappy charger, other than the odd freeze, fixed by reset button. Any help appreciated. The charger I bought was one with a AA battery which has a USB connection.