Please Help: Update may have bricked my HTC One M8

[BearsFan17]

To start off I have a non rooted phone. Last night my phone downloaded the OTA update and it started installing it overnight. But when I woke up to see if it was updated, the lockscreen is black and I can't get past it. And my phone keeps restarting to try to fix it but it's always stuck on the lockscreen like it's in a loop.
I've tried going into recovery but when I try a red triangle with an exclamation point comes up. I know I can factory reset my phone via the bootloader (I think) but I don't know how to backup my stuff especially with my phone in this state. PLEASE HELP

Here's a photo of my phone screen if it helps.

 

[Rukbat]

Bring it to your carrier and tell them that the update bricked the phone. Their update, their problem.

 

[TwitchyPuppy]

Bring it to your carrier and tell them that the update bricked the phone. Their update, their problem.

And they'll charge you for it because the phone is put of warranty.

So it's best to wait for someone who knows what to do.

 

[Golfdriver97]

When you reboot to recovery, try holding the power button and shortly after that click the volume up button. That should bring you out of the 'No command' screen.