Digital Gee

I got a flat today on my Continental GatorSkin rear tire. I was on this really bumpy road for a short distance, and noticed the bike was vibrating far more than usual. Got off, looked at the bike and saw nothing amiss.

Shortly afterwards, when I was on smooth pavement and the bike began handling poorly, I checked again. Sure enough, back tire was losing air. But I could still ride it, and I was only two miles from home, so I rode it slowly back home. Only problem was when the edge of the road was not level -- then the bike started to slide out from under me from the back.

Anyway, I got home. Tire completely flat. I'll change it later. Two questions:

1. Was it a big mistake to ride the bike with a flattening tire? Have I probably screwed up something else?

2. How hard are Continental Gatorskins to take on/off?