What Could Cause A Popping Sound In The Back Of My Head Followed By Neck Tension And Head Pain That Worsens With Activity?

I was doing indoor sports and suddenly heard a pop at the back of my head. It wasn t painful. Later on it was accompanied with uneasy tension at the back of my neck up to my head. If I should do sports, the problems aggravates. Now to clean ordinary floor, will cause serious pains in my head and ears. Even sports by walking is a problem at this stage. What could this be?