stiff rear wheel

[Wheaton Jr.]

I recently replaced the front sprocket nut and the bike and torqued it down. To do it, I put it in neutral and had somebody step on the rear brake while doing so like the manual says. Now when the rear wheel is in the air, I rotate it, but its really hard to spin. Could something have happened because my friend was stepping on the rear brake really hard? I took it for a ride to see if it would eventually work itself out but it's still bad. When I move the wheel itself, there is a noise coming from the rear brake caliper. I was wondering if you know where I should start to get this fixed, thanks. David.