Default [Q] can't wipe data, 'no sd card' and cant revert to stock

Hi guys,

I recently traded an iPhone for a nexus 5 and I've been loving it except I've been having an issue lately. The phone was flashed with a custom rom and kernel. I had a couple of issues so I attempted a factory wipe via cwm but it seemed to freeze when it says 'wiping cache' etc. so I restarted the phone by pressing the three buttons and now I can't save anything to my phone (it says no sd card) and I keep getting 'google play error reports' and I cant access the camera.

I've been attempting to flash to stock in hopes that it would solve the problem and that I could get updates OTA in future so I downloaded 4.4.2 and managed to get the adb and fastboot files working via nexus root toolkit. When I attempted to flash the rom onto my phone, NRT reboots my phone into fastboot mode and a script comes up saying 'it should take 5 or so minutes' and 'press any key to finish' - except my phone is doing nothing but showing the regular fastboot screen.

So I've looked all over and found a method posted online that uses cmd to flash it but I need a file called something like 'hammerhead434839.img' except I cant find it. I figured that it would be in the recovery rom I got from google so I opened up the .tar file but there is only one file inside.

Theres another method I found that uses some 'flashall.bat' but I am not sure where to find it.

Does anyone have any suggestions? I'd really appreciate it as I cant even make or receive calls or texts anymore. thank you