I'm obviously a noob.
I flashed my nexus 5 and everything seems to gone. Google apps keep popping up with a message "Unfortunately Google Play has stopped working" and all othe google apps pop up with same message. I can't do a factory reset. I can't flash from the terminal app on mac because I can't put the phone into usb mode. I don't have a usb sd card reader. I don't know what to do.