Coup contrecup?

Hi everyone,

A couple hours ago, I hit one side of the back of my head on a door, and shortly after I developed a mild pain on the opposite side of the back of my head. The impact wasnt very forceful, but I fear that I might have gotten a concussion. Besides the pain, I dont feel any other symptoms such as nausea, dizziness etc. I will talk to a doctor later, but until then, do you think it might be something serious?

Thanks