Cold Start, Brake Stuck

Got in my truck this morning. Started up fine. Released the parking brake and shifted into reverse (MT) and eased off the clutch. No movement. I could feel the truck "tugging" as if held back by something so I figured I had forgotten to release the parking brake. The parking brake was indeed disengaged, so I got out to check if there were any objects wedged under my tires (I've occasionally had this issue as there is a rock bed near my parking spot, sometimes one gets dislodged and finds its way behind a tire). ...nothing. I get back in the truck and really try to give it a good jolt to get moving, rev up to 2500rpm and give the clutch a good "kick". I can feel the truck "tugging" and even feels as if the frame is being "torqued" but no movement. I scratch my head and for the first time try depressing the brake pedal. As soon as I apply pressure, I head a slight "pop" sound from up front and now the truck will roll. I went for a short test drive and observed no adverse conditions.

Can anyone explain to me what the hell I'm dealing with?

Edit: More info. It was 50F outside and dry. I don't think it got below 40F last night and it's certainly been colder than that recently without having this issue. Brake lines appeared to be connected with no noticeable leakage. I did observe fresh grease that appears to be leaking out of the boot on the Front Left CV joint. I'll get around to fixing this but I can't imagine it's related.

 

Sometimes corrosion can "hold" the brakes like this (but I dont think EVER to 2500RPM), or possibly a sticking caliper (Which given the amount of gas you gave it) might be the case. This the first time it "stuck" like this?

 

Yeah, first time. It’s a relatively new caliper, maybe 2-3 months old.

 

My guess is stuck parking brake.
Check your rear brake condition/shoes/etc. Are the plastic grommets where your parking cables go into the rear drums broken? Can you pull the drums and have a look around?