ladies, can you give me some help here?

Ok, so I took this girl out on Sunday...watched fireworks, had some drinks, shot some pool. we laughed, ect and were very comfortable around eachother. i jokingly gave her a couple of chances to end the date early if she wanted to and she said no, that she was having fun. the date ended after about 4 1/2 hours and we went our seperate ways. i texed her to make sure she got home ok and she said yes, thanks for checking. i texed back, asking if she had fun. short answer, she said yes. i texted back, enough fun for me to see you again? she made a joke and said yes. i texted have a good night.

so the next day i just send a couple line message to her thanking her for a good time and that i'd talk to her soon. nothing back...ok, thats fine...ppl are busy. i get that. no big.

later last night i gave her a call and got her voice mail. i just left a quick message saying who i was, my number, and to give me a call when she had some time. nothing back as of yet. again, during the week...may be busy, ect. ect...

i'm just wondering, why would she (after having plenty of opportunities to back out at various points) agree to see me again and not get back to me? I mean, I'm going to wait and not contact her again...atleast for a few more days if at all. maybe i could've contacted her too soon after the date, but that waiting 3-5 days crap makes no sense to me. i mean, she said yes to see me again before this.

so i'm just confused. i haven't dated in a while and i really don't see what i'm doing or have done wrong. i could be making something out of nothing. just trying to get a little insight here. much appreciation.