Search Results: not dating material

This situation started at the beginning of the school year back in August when Girl 1 was interested in me but I did not know her so I could not recipricate that interest. My friend told me about her interest in me and I communicated to him my disinterest in her becasue of my lack of knowledge about her. I imagine this information was later communicated back to her in some shape or form. Meanwhile, I got interested in Girl 2 because we'd been good friends up until then. Throughout the following months me, Girl 1, and Girl 2 had hung out, talked, and texted with me getting to know Girl 1 better and better as time went on. One day Girl 2 calls me after bringing up wanting to ask me a question. She's nervous the whole time we're talking and I can tell she's trying to ask me out. I end up actually doing the asking Girl 2 out after we went over the whole I like you, you like me exchange. Thing is, after a week of dating I realized I didn't like Girl 2 any longer that the initial feelings that were there weren't there any longer, and Girl 1 seemed like a much better option now that I had gotten to know her.

Now I don't know what to do. The fact that I don't think of Girl 2 as girlfriend material doesn't mean I don't still care for her. I feel like I would hurt her tremendously if I broke up with her and went on to date Girl 1 afterward.

Note 1: G1 and G2 are friends, not on good terms, I have learned, since I've asked out Girl 2 but still friends.
Note 2: This is my first girlfriend and I don't want to fuck up too much. I would say that I don't want to fuck up period, but that's clearly not a possibility at this point.
Note 3: Both girls are great, I just don't feel like I have anything in common with G2. We have different interests, we have little to talk about, and our conversations turn to stupid arguments (not like legit arguments just like: What makes a GIF funny etc.) to fill up space. G1 I can actually ho