The symptoms are real. I've had "head sensitivity" to the extreme as well.

The mental anxiety in response to the event of bumping your head makes symptoms worse in the brain. That is, the mind causes physiological effects both healing or health demoting. This is almost always the major factor at play.

Bumps are not concussions. The word 'concussion' is a mislabeled term anyways. Generally speaking, concussions are significant forces that damage the brain. That being said, these bumps are real and cause symptoms that can increase symptoms. They can feel like a brain new concussion. Trust me, I know this all too well.

Think of it like this: when you get your ankle sprained it is sore and swollen. The healing process may ebb and flow with symptoms of pain, inflammation, ankle mobility, strength, etc and your ankle may feel as bad or worse as the beginning at times, but in reality, your ankle has improved over time. The brain is very similar. The original concussion caused your brain to be a bit swollen, lose some function, and it sometimes hurts when you are rehabbing it. But over time, are you healing?

I never had luck with my brain just healing on its own like many people. I actively do things to help keep my environment inside my skull as healthy as possible for healing and sustained brain power along with healthy amounts of mental stimulus, exercise, social life, infrared light therapy (~$40 for an incredibly helpful light vs. $$$$$ for office visits), diet, supplements, sunlight, nature.

My brain is doing well now for the most part. I also had bad brain senstivity, but just know that it is what we do not know that we fear. What makes this brain sensitivity so scary is "Is this a concussion?" Unless it's a big hit no. Does it cause symptoms, yes. But your job is to rewire your nervous system to calm down, move on with your activity, and not let your anxiety take over. Meditation helps me greatly.

You got this! The brain is an incredibly resilient organ. Each person can heal it with good, quality efforts.