Nokia :: N95 - Phone Switched Off / White Background Comes Back On

My mum only gave me this phone 2days ago as she got a new one. She's never had a problem with it and has kept it in a hard case so still looks brand new. I always have a habit of breaking or losing phones, this is 3rd one in 4 months. Anyway I picked my phone up and it was switched off but I presumed it was dead as I had left my music playing. I put it on charge only for 10 minutes but I never tried switchig it on as I forgot to take it out with me. I put it on charge again last nite but it won't turn on this morning. The screen comes up white with the battery sign on the right which stops after a minute as I assume its fully charged now. Its not the charger as my bf uses it for his and the phone does seem to be charging. The on button can't be broken as when I press it the white background comes back on. I've tried the hard reset wth the 3 * and green button but nothing.