What Causes Pimples On Pubic Area And Chins 2 Days After Sex?

I had sex the other night and two days later I had two pimples on my mons pubis and two on my chin, there are now four on my mons pubis. They are red and have whiteheads, I squeezed two of them now they have dark heads, they are also pretty painful to touch. Could this be something other than pimples? I rarely get pimples anywhere and this sudden outbreak has me concerned.