I would try and get to know her more without you both using the term "dating." If you said yes, that meant that you have feelings for her or didn't want to hurt her feelings. I'm going through this whole "dating/relationship" thing for the first time for about two months now. In the beginning when I was dumb, I jumped him with the question asking him if we were dating. He said yes but a couple weeks later he came out with the truth and told that he couldn't date me anymore because he had been cheated on twice in long distance relationships but still wanted to get to know me. I was totally fine with that because I just thought guys wanted to say they were dating a girl as soon as possible but now I know from him, and you, that not all guys are like that. Now we've spent these past two months getting to know each other and we've become really, really close. I was like you, thinking that no one would ever like me and I wasn't the one to make the first move on a guy. Either he had to do it or there was nothing. Lol I would get to know her more on a friend level. If she really likes you, she'll accept that and not just flip you off because you said you wouldn't date her because you need more time.
(Sorry for my story. I didn't really know any other way to explain it. Lol)