Is this wrong? or okay?

Okay so there is this girl I like and have been trying to date since, around February. I finally got the courage to ask her out in May, but was turned down. I didn't give up though, I continued to talk to her, but she just didn't show any interest. I really want to get together with her, but here's another problem...
I recently discovered these last 2-3 days that I also like someone else, and this someone else is also a friend of the girl I like. Since I got turned down from the first girl, would it be wrong for me to try with the second girl? Or would the first just kinda find that a slap in the face?