Nexus 5 Not Booting up, Can't get into recovery mode, Can't Flash it.

[AC Question]

Hey guys, so I bought this Nexus 5 that was supposedly working with a broken screen. Replaced the screen, but the phone won't boot. It goes into the 4 circle animation thingy forever. When I go into fast boot and I try to use recovery mode, it says no command and after a few seconds restarts again. I can't use the power button + volume up to get into it, just nothing. After that I unlocked the lock state and tried flashing bootloader-hammerhead-hhz20h.img and that gives an error "failed remote:flash write failure." Is there anything I can do? I'm pretty sure I bought a dead phone.