How can I deal with extreame embarment?

At prom, my boyfriend kissed me on the dance floor. I wasn't expecting it, so I didn't push him away. Right after, I told him not to do it again, but the damage was done. The girls at school think I'm a slut, and a teacher came up to me and warned me against further PDA. I have never been so embared in all my life. What can I do?