Alright, so I messed up. I tried to SBF my 621 device down to 605 (stupid mistake, I know) and now it's stuck in the bootloader. The screen reads as follows:
My main concern is that I'm unsure whether or not my phone is charging. After that it's a matter of exactly how to get it back to factory state. It was in factory state prior to trying to SBF it down to 605. Shouldn't I be able to just flash it with 621? Or is there another fix?