Why Won't My Samsung Galaxy S4 Turn On?

[AC Question]

The phone shut down as it ran out of battery, I tried holding down the power button down about 20 times before the lock screen turned on. It lasted about half a second but I managed to see that my battery was on 6%. It's definitely not flat... Every time I hold down the power button it shows the Samsung logo then turns off or loads to the lock screen then turns off. I have no idea why.. I have also tried tapping the back of the device as it turns on and that seems to work a bit... Please Help?!?!?!

 

[anon(632115)]

I know its not easy to but let the phone charge for 30 minutes before trying to boot it. Allowing the battery to discharge fully doesn't do it much good