As I said, your concern should focus on taking care of your brain. Nobody can answer your question. It all depends on the magnitude of the injury and how your specific brain responds. For those who see a delayed symptomology, it usually does not show up until later in life, like the 40s and 50s.

Many of us have had many concussions. I've had 14 or so. I did not see a noticeable problem until my 13th and 14th concussions at 41 and 44. But, I learned early in my life that I needed to avoid stressful situations, including stressful occupations.

For many, they can live symptom free except when they are in a stressful event. Anxiety about "what if" from a past concussion is such a stressful situation.

I am missing part of a finger and thumb. Do I stress about it ? No, I just go on with life.

I have deteriorating osteoarthritis in my hands. Do I stress about it ? No. I go on with life and take care of my hands to slow the progression.

Stressing about what the future holds as a result of unknown bumps to your head will make you miserable. As I said, you could have suffered 3 concussions and never have a problem. Nobody can say.

The facts are quite simple. People who develop neurological problems with memory and such usually have a history of some sort of brain trauma. But, not everybody who experiences brain trauma develops neurological problems. There is an increased "probability" but nothing that says problems WILL develop.

You could develop neurological problems with memory and such from poor sleep like that caused by anxiety.

So, stop trying to find a problem to worry about when none exists.

As I said, What would you do if the baseball did some damage ? How would that change your life at the present ?

Try to put that concept in perspective. I had 8 concussions by college, one required 3 days of hospitalization. I'm 62 and my IQ tests in the top levels. I have some visual processing issues but I can do just about anything I want.
I knew I had brain damage at 15 but went on with my life with my only limit being no contact sports and reducing stress.

Everybody should be trying to reduce stress.

So, what are you going to do to move forward ?