Camera isn't following mouse the way I want it to (akin to nuclear throne)

In my game, I want to have the view follow my mouse, like in nuclear throne.
Here’s what I have so far:


Here’s what it looks like in game:

GRRRR

It’s mostly working fine, but everything to the left of the robot is complete jank. Also, up doesn’t go as far up as I want it to. help?