Engine developed a 'stumble'

I have not been able to drive my car very much lately. Too hot and I just moved. So when I do drive it, I tend to REALLY DRIVE IT!
Today I needed some welding done. After the work was finished the guys that owned the shop pointed out that they had a burnout box on the premesis. Well I had to try it out.. show off a little.
I did a 2nd gear dump and went into tremendous/violent wheel hop. I get out of it right away. Do a 1st gear dump and bounce off the rev limiter while the tires melt miles off .
As I am leaving I notice that I have picked up a very slight miss. But under a very light load its barely perceptable. I know something is not right so I slow down and put the car into 4th to drop RPMs to about 1400 and put my foot to the floor. It lugs/shutteres as if 3 cylinders are dead.
What happened? Could I have tapped the plugs with the pistons and closed the gap? I never had problems before taking it to 6300 RPMs.
All my info is in my sig.