Hi all. After using Sony's method of unlocking the bootloader, I flashed a version of CM10 (FXP224 I believe) and all was fine, but unfortunately the 'home' button' didn't work, so I got a new ROM and flashed that(Another CM10 build). The second ROM changed the recovery from CWM to TWRM for some reason (not sure if that's important) and now my phone won't charge. With the remaining battery, I flashed every compatible ROM I could get my hands on, hoping to fix the problem. Now I have a phone that is too dead to turn on at all, and will not go into DL, fastboot or recovery mode. I currently have the stock ROM ready to go (Was hoping this might fix the issue), but an unresponsive phone, and I'm not sure what to do. Trying DL or fastboot modes causes the light to flash red three times, indicating no battery.

Additional Info:
Currently it has CM10(FXP 244) on it.
When it had the ROM with TWRM, if the phone was turned off, it would bootloop until I flashed the ROM again.
Phone works fine (apart from the usual GSM issues with this phone and CM) when it does have battery.

Any and all help is greatly appreciated.