Okay I just dyed my hair about four hours ago.
The color it should have turned out to be was a medium brown color,
But now it's a really dark brown, nearly black, shade.
My original color was a light brown shade.

My hair now also has areas are lighter... so it's all patchy.
It's just horrible.

Now I have two options...
I don't know if I should just dye my hair all over the same color to correct the patchy sections, then just wait for it to fade and deal with the bad color...

Or if I should try fading it now, without reapplying the color.

And how soon could I do this? Because I literally just did it hours ago.

Please ANY advice would be so greatly appreciated...

Try fading the colour out with a deep cleansing shampoo, pantene do one. And then after a couple of washes, if it's faded a bit, then perhaps try using an artificial colour remover like colour opps by L'oreal. You may need to use it a few times though to get the colour out.