[Tech Support] Help, May Have Bricked Phone!

So, I may have done a bad. I attempted to install Cyanogen mod on my Vodafone HTC One M8, following the exact instructions on there wiki page, even using their recovery. When I rebooted the phone it played the standard boot up animation, did the "upgrading android" animation. Then it shut down. It now will not turn on unless I plug it in, when it will do one of two things. Either it will hang on a photo of a battery, or it will hang on that with the red text at the bottom. It always does the latter when plugged into the wall, and mixes it up when plugged into the computer. If it is the latter I cannot turn it off until the battery dies, but in the case of the former it waits a few seconds then powers off. No combination of buttons will turn the device on. I have backups saved, so if I can get into fastboot I can easily fix it.

Side note: Being able to get it into a warrantyable condition is fine, but obviously not preferable.

Thank you in advance.