My phone won't turn on

One day my phone started playing up.iv only had it 8months.it doesn't turn on fully.it would start up and show samsung and go blank after that and not finish loading.it vibrates and the blue or red light flashes which would flash green at times.wen it charges you don't see the green or charging indication.the two buttons either side of the home button light up white. It doesn't have condensation or hasn't been water damaged.although the phone has been dropped once before it never affected it's performance .does anyone no what the problem is and way to fix.i knw it is not the battery as I have tried someone else's and it never fixed problems.before it stopped turning on it would turn on and startup on the odd time and let me use phone for about 20mins before it would turn blank and blue red light would flash and the white lights would light up .I wud turn phone off pull out battery and let sit for 20mins n put bak in it would start up again.but now it's not even doing that.and also can anyone tell me can u get ur photos off the phone using USB cord to computer without it being switched on cos so far I've been unsuccessful ,computer doesn't read device when it is plugged in.?I have 2000 photos stuck on my phone..some are of my 12yr old niece who recently died so I don't really care fr the phone anymore I jus really want my photos if sum 1 knows how I can get them off..thanks any help or reply will b appreciated