Dispell?

Okay, so I performed a spell today in order to solidify a scenario I am currently discussing with someone.  I used a piece of paper (a print out of one of his messages to me), some of my blood, and I wrote my spell on the paper in pencil.  As I waited at the metro for a roommate to arive tonight, I took out the piece of paper again and went over it a few more times.  As my roommate gets in the car, I noticed a man flash his hand (palm) to me.  He was getting in the car that was in right in front of us.  He flashed it again at me (a classic *poof!* mannerism), two more times and got into the car.  My roommate witnessed this, and simply brushed him off as bring crazy.  It looked like mentalism.  I NEVER cast spells, but I'm highly interested in magic... I flirt with the ideas, and I have manifested before (with my mac's iphoto), but I have never actually used my blood for a spell.  I see a lot of strange things from people, but never anything that looks like direct energy transference.  This hardly looks like a coincidence.  I doubt it was actually the man who was getting in the car... it was probably something else, going through him.  That was just... new.  And I thought I've seen it all. 

Has anything weird like this happened to anyone?  Anybody here practice magic?