Victor,
Congratulations on your first couple of flights. Great stuff ain't it!

You WERE lucky with the prop. I had it happen once in the air (with my trainer when I was learning). The engine spun up to about 20,000 rpm.

Fortunately, the instructor knew immediately and shut it down, so there was no damage. Unfortunately, it took me almost two weeks to get a new prop nut. No one had them locally.
Dennis-