I did something a but silly... My phone battery doesn't seem to last long enough when I'm out on a night. The phone is generally flat by 3am so I had a brilliant idea and bought a spare battery. Awesome. So the next day I charged up the phone and when it reached 99% charge I swapped the battery (I discovered that if you change batteries while it's still taking on juice it doesn't turn off). This was foolish however, as it now shows 100% charge for aaaaages, nose-dives down to 1% over the space of about an hour and then stays there until dead. It also refuses to charge while on 1% battery unless the phone is reset. Short of a factory reset, what can I do?!