Am I a slut?

[ Vote ] I feel horrible because I told this guy named Adam I liked him before we left for Christmas break and he told me he liked me back but I told him I wasn't ready for a relationship and wanted to remain friends. During break this guy named Liam (that I used to have the biggest crush on) kissed me and I kissed back. When we get back from break the Adam told me he can't get over me and now I feel horrible. Does this make me a slut? Should I tell Adam? I still have a thing for Liam and am completely over Adam. What do I do?