Kenneth Romeo Carrington

Is there any way I can check to see if I accidentally set this? Some sort of command maybe?

I made my way to every place I found copper nuggets. I dug all the dirt in the area, and even mined out some of the stone, yet none had copper underneath. I am about to break my copper pick and feel like I am wasting my time. 

I seriously do not want to have to explore for more surface nuggets, but not finding any ore blocks underneath the surface is equally annoying. How deep do I have to mine?????