Lesbian

Ah, okay. About a month ago I befriended a girl because I thought we might have similar interests, based on how she spoke and texted. When we introduced ourselves and what we like and such, I realized that I did not like her very much and personally I don't think we clicked. Anyways, one of the first things she told me was that she is lesbian, and I said I support her. My mistake was not telling her that I am straight. She recently has been making it very obvious that she likes me, and I literally cannot tell her that I'm uncomfortable with that and I don't want to talk anymore, because I don't want to hurt her. What should I do?