Stuck on apple logo after screen replacement

Replaced my iPhone 5's screen which is something I have done many times before a fairly easy procedure. But this time after installing its stuck on the apple logo and wont boot up past that. I have opened the phone back up to check everything was connected properly and I'm fairly sure it is. My next move was to restore the IPhone in recovering mood so I tried that and its come up with a mix of error (9) and error (21). I have tried updating iTunes, tried a different computer, different cable, different usb port but can't seem to get anything to work. I didnt have any issues with this phone prior to replacing the screen. Thanks in advance to anyone that can help.