That's a very common type of dream. I used to have dreams where I'd be fighting, but all of my punches were super slow and ineffective. The punches that hit me didn't hurt at all either. It's been years since I've had dreams like that. Now if I dream I'm in a fight, I usually beat the shit out of someone in them. Another one that I still have once in awhile is where I'm getting ready to bang some hot chick or go on a vacation or something cool like that, and I'll be packing my clothes or looking for something and I keep getting delayed and never end up making it to my destination.