My blackberry old 9900 won't turn on :(?

[Jmjmjmjmjm]

I'm having a little trouble with my bold 9900, it has been constantly just restarting and randomly switching off at 50% battery. So I decided to update it overnight and when I woke up it just will not switch on and I've put the battery in and out and the red light comes on but turns off then doesn't do anything. Is there anyway I can reset this somehow?!