Confusion

Ever since I've been clean, (also counting my last 3 day streak) I noticed that I've been observing the bodies of the girls around my school a lot more. I literally told a group of friends that I never noticed how many beautuful women we have on the campus. They gave me shit for it, but that's besides the point. There's this one girl that I'm friends with who, almost any time I talk to her, I get hard. I think I like her, but we've actually talked about our relationship, & she's not that keen on dating one of her friends because of something that happened the last time she tried that. She also told me "whatever happens, happens," so I don't really know what to do with that info. I guess the question that I have is if any of these signs of a greater problem (me getting hard & looking at women's features more often) or if this is normal. I'm 17 if that helps. Sorry about the poor phrasing.