An on and off mild headache does not mean much. When people ask about headaches and I write a reply, I often get a headache. Yes, literally, I get a headache. The mind and brain can do strange things. Just a bit of suggestion can trigger symptoms.

Many of us have had chronic on and off headaches for years. If I got concerned with every headache, I would never have time to live a life.

I bet you looked/checked for symptoms from your head bump. That is a common response to a head bump for many with PCS. Find something to distract yourself and you will be better.