I installed adsense on a few sites. Since my girlfriend and I run sites together, we share one adsense account. (all of our stuff is on the same IP)

Today we added a code to her site, and then we went out for a movie. Came home, and in about 6 hours time her site had earned $13.

I noticed that the ads were from reputable places, like ORBITZ and some other big companies. Do they have a higher click pay rate? What determines how much an ad click pays? Will she be penalized for so many clicks in such a short time span?