How do you reject a date kindly?

i need to turn down a date, but i did 4 stupid things, gave him my cell #, my school, major, and my work place, i'm so stupid i know. He goes to my school in the same building as me and is a music major. What should i do? We might have a lot in common and I know he's not a pscyho, but I have a bad feeling and feel I should decline before we actually meet this wednesday, having only met this past Monday. I don't think platonic friends is what he is willing to stick with. I would rather back out now then be sorry later. Help!