Do i have a mild concussion?

Your parents are over looking how serious this could be. You could easily be suffering from a injury to the brain, this is one of those things, that you don't just wait and see. That your having symptoms, has to be considered a problem until proven otherwise in this situation. They need to take this more seriously, and you should get checked right away. A quick MRI will show what's what. Yes they aren't cheap, hopefully you have insurance or some sort of medical coverage.