Painful inflamed pimple on belly

Hello, anyone experienced pimples growing on their tummies before? I’m in my 20th week and there is a single large pimple that is quite inflamed and painful to the touch on my stomach. I’m not quite sure what to do with it - what is safe to apply etc. Also a little worried it will affect the baby. My appt with KKH is not until next week, but the inflammation seems to be getting worse by the day..