Buzz cut in the work place?

I am a 20 year old butch and I recently shaved my head and I absolutely love it. I am starting a professional summer internship in a month and my mom has told me that my haircut is “unprofessional”, “disrespectful”, and that I will never get a job after college if I don’t grow my hair out. The company I’m working for is based in DC and seems pretty liberal. So is it unprofessional if I have a shaved head in a corporate office?