Nexus 7 tablet stuck in boot loop

[anon(10400412)]

So I found this Nexus 7 tablet running really slow, so I decided to manually flash Android 4.1.2 onto it, thinking it'll speed it up. I successfully completed the flash (I think) but now when I go to boot up the tablet, it gets stuck on the Google screen. When I hold the power button, it just restarts and gets stuck at the same spot. Holding the power button and volume up doesn't help either.