Are your brakes dragging or binding? Check the following:

Caliper seized or damaged 

Inspect the calipers. If they have been damaged then they will need to be replaced. 

It is possible that the calipers have seized, remove brake pads and check.

Inspect movement and replace if necessary.

Park brake not releasing correctly 

Inspect the handbrake system. 

Ensure that the handbrake releases correctly.

Check handbrake cables for damaged and/or corrosion.  

If not, it can cause the rear calipers to grab the discs. 

Adjust handbrake cables if necessary.

Damaged or crushed brake pipe 

Inspect all the brake lines. 

If any of them have been damaged or crushed, they need to be replaced.

Pedal linkage 

Inspect the pedal linkage to the brake booster. 

Ensure that there is a 2 mm of free play in the brake pedal before the pedal activates the master cylinder. 

If there is no free play, adjust linkage.