Xperia :: X10 Mini Pro Won't Charge

The battery was about 10%, and I was downloading a game. All of the sudden, it froze and after a few seconds it turned itself off. I triend to turn it on, but I couldn't, so I thought battery died, and I left it on the charger over night. In the morning, it still couldn't turn it on, and anything I triend didn't work.When I press and hold the ON/OFF button, it just vibrates shortly and nothing happens. If I repeat that, it won't even vibrate until I pull the battery off, than put it back, and try again. Won't charge on the charger, won't charge on USB cable, won't turn on. I don't know what to do, I already tried Hardwer Reset (with and without charger) - didn't work, tried connecting it to the USB and holding the BACK button - still nothing. Sometimes, when I try to turn it on, it won't vibrate, and the red light flashes (that means the battery is low, right?). Sometimes it doesn't react at all, no vibration, no red light, nothing.