It’s too bad you didn’t talk to him or get to know him before you kissed him. Now you’re just some chick that he kissed, not someone that he knows. He’s probably kissed lots of girls and probably slept with some of them (I’m guessing that he was probably trying to get you to have sex with him too, and it sounds like that is all he was interested in).
I agree with @zenvelo that you might send one text and see if/how he responds. If you don’t hear back from him, then chalk this up to having this one bad experience and try not to repeat this particular type of experience with anyone again.
If he does respond, it completely depends upon what he says with regards to what you should do next.
If he doesn’t respond and you have to see him somewhere, like at school or another party or out and about, just try to be polite and cordial, don’t go all emotional on him, don’t try to find out why he ignored you, or you will make it much worse.
Then next time, have a game plan in mind before you ever get to the point where you are tempted to kiss and “score” with a guy. Your best bet is to get to know a fellow a little bit before you ever find yourself in a situation in which kissing is involved. Don’t let total strangers (or guys that you know, but don’t really know) kiss you or touch you in a sexual way.
And don’t let anyone (guys, girls, or your own friends) make you feel un-cool for not participating in the kissing and carrying on.
If for some reason you end up having a conversation with this guy (or anyone else who might bring it up for some reason, like someone who saw you kissing him) maybe you could say this, “I enjoyed kissing you Tom, but I shouldn’t have let it get out of hand. I shouldn’t have done that.” Then leave it at that.
The other thing that stinks about this whole situation is that it is still common in this day and age for a girl to get labeled as a slut, whereas the boy, who was participating in the same activity, gets labeled as a super-cool dude. Girls still have to be way more wary of what they do, and what they say.
For the future, have a game plan, a plan B, and a safe exit strategy : )