Sometimes the track pad gets stuck, but I was using the wrong screwdriver's to get out the old screws and lost a couple. Bought the correct screwdriver, shuffled things around and good to go now.
Buy the right screwdriver and have a small box for your screws.
MacBook Pro 15" Retina (Mid 2012-Early 2013) Screw Set
P5 Pentalobe Screwdriver Retina MacBook Pro and Air