Dodge Caravan Breaks keep sticking?

We just got new break pads and rotors on our dodge caravan a few weeks ago... now when in the morning we back out and once put in drive our breaks stick, and then it cant go in reverse for a min. or so after that they work alright but sometimes they get a little jerky and squeeky.... and then the next morning same thing and even worse if we let the van sit for a whole day....