Problem with Google Play services
to solve your problem you need to flash the Gapps again follow this steps 


Download the minimal Gapps from here this zip is for 5.0.x roms and contain the needed apps (including google play services) and libraries every thing else you can get it from the play store.
reboot to recovery and flash it like you flash any other mod or rom (no wipe needed)
after installation the first boot may take a while since android system needs to update the dalvic cache (now its art and it takes a little longer) so be patient :D .
Now the google apps should work just fine.