Sony Ericsson W910i (can't load new Firm wear)?

Hi all, This is my First Post so please take it easy

Ok, I have a W910i that has started playing up a few weeks ago (turning its self off mainly at the most inconvenient moments), I started reading up about how to fix it the last week i started getting a Charging error.

I thought as the phone didn't appear to be charging properly the Wall charger must be faulty so i bought a new one which didn't fix the problem, yesterday i was using my phone with 1/4 battery life when it turned off and i couldn't get it back on. Now when i put it on charge the red light comes on and there is a ticking noise coming from the ear speaker, i have also tried to plug it into my computer in an attempt to get some stuff off it but the computer doesn't recognize it (probably as its off) and this time the red light is on but there is a Buzzing through the ear speaker.

I am now left in a situation where my phone is not working and the shop i got it from doesn't want to know making up excuses that because its 8 months into a contract i'm trying to get a new phone out of them???

I did some reading up and it looks like my Firm wear needs upgrading but the problem is i can't tell if the battery is fully charged even though a mate charged it up in his phone and the SE web site Updater won't run past the "Press C down and plug the USB cable in" Part.

So can anyone point me in the right direction?

Thanks.
Chris