Dirty talk with a stranger, feeling dirty....

Not sure what I'm doing, met someone on an online dating site and ended up having quite graphic sex talk on msn, never have done this before. We have exchanged pictures (against my better judgment) but there is also something so darn exciting about the whole thing. It's actually quite hot! We've talked about meeting, we've also done some small talk and know a little about eachother. Am I crazy for even doing this? or even thinking of meeting this person? This is my first time doing somthing like this but probably not his, I'm not deluded about that, it's risky but part of me is just so excited by the whole thing. What do you all think? Is it normal?