If you drained all the oil till nothing was coming out, then why do you think you over filled it? (was the truck in a weird slope or what?)
Not sure how much you spilled, but your truck could be burning a very small amount of oil, so exactly 5QT wont come out. How much came out roughly?

 

I was on a slight slope facing down hill.

I am guessing that 4.5qts came out.

 

What I usually do is put 4 quarts in it, run it a minute, let is sit then top it off until its between the low and high mark.

 

Next time park facing uphill and don't forget the oil in the filter to account for what doesn't come out of the pan.