My Nexus 5 won't turn on or charge

[AC Question]

My phone was working fine this morning. It had a almost a full charge like 90%. I left it on my desk and came back two hours later. I pressed the power button to look at the screen and it stayed black. I tried again with a longer hold nothing. i though maybe the battery had died so I plugged it in. It doesn't even show that it is charging. Completely dead. I followed all the steps on Google's support page and still nothing. I've tried what other people have said with the tapping in on a hard surface, volume plus power. There was no indication that something may be wrong with the battery it always lasted all day even when I play games on it. Could this just be that the battery is completely dead and it gave non of the warning signs?