Kissing strangers

I've had my fair share of make outs, mostly of guys I've actually known. Two weeks ago I met this guy and we really hit it off and I didn't feel weird or one ounce of guilt for spending the night with him. But here I am a little tipsy I just made out with a guy in a nightclub (first time kissing a guy in a night club I had no intention of doing so either) and it lasted about 10 seconds until I finally said it was enough and I feel so dirty and just gross and all we did was make out! I don't know what's wrong with me, why do I feel so nasty? I actually am so upset with myself right now