Whats up with this 19 yr old girls?

I'm 23 and I met two girls on the same class, they both are 19, they dont like each other so it's ok that I'm talking to them, the first one was cool we hit off but ove day she I was studying for a huge exam and I told her she was annoying the crap out of me and she let me be the next day she didn't talk to me, and I asked adkd her why not and she told me because of what I said and that got me mad and I told her not to give me that **** and now she won't answer my text, anf the orget one takes like almost an hour to repley muy text, I know they both like me, I mean im ove of the better looking guys in school and have a nice physical body, not to soinds all cocky and I'm great with every one I talk to all sorts of people, im not concided. is there something I dont know about this new 19 year old?