"Downloading... Do not turn off target !!" on boot after flashing boot and recovery.

[Richard Buettner]

I mistakenly flashed my boot and recovery using TeamWin Recovery. I now get a "Downloading... Do not turn off target !!" message when I try and boot. If I try and boot into recovery, I receive the same message after getting the blue text in the top right of the screen. I have root. Is there any way to solve the problem, of have I royally boned my s4?