It sounds awful. Laughing at you? How rude.
As about being called miss, did you make it known that you want to be called doctor rather than something else? Some of my colleagues have PhD and made it known that they want to be called Dr. Yet there are some that made it known that they absolutely don’t want to be called that at all. I don’t believe people should just assume to call you Dr because you have PhD. Make sure you introduce yourself as doctor and have it in email signature, sign on the office door etc and correct people, if that’s important to you.