DTLT please input so I don't mess something up!

Just installed the DTLT headers and have yet to install the URD o2 Sim. I'm not pulling a check engine light so I thought I'd test drive my new pride n joy down the street n back. Started to reverse and I noticed my brake pedal needs to be pressed pretty hard to brake. My truck has been sitting for about five days because I stripped the two front oxygen sensors and had to wait till I received the new ones. Could the brakes be to the sitting? I don't want to F something up so I'm counting on TW to give me a little insight before the test drive.

 

Damn! I barely have any brakes. WTF? no clue how this could happen. There stiff as hell!

 

Its' funny you say that lol. I kinda, sorta, might have hooked that hose up to another location. So... switched em and my brakes work. I'm an idiot hahah. Hey, I never claimed to be a mechanic. Thanks alot dude!