I remember when my husband told me that I was talking like a teenager. It made me cry. But I really couldn't put words together well and I couldn't follow conversations.
A concussion causes a lot of strange symptoms. Those of us that have been through it understand.
It can also change your expression of emotions, including crying easily.
If you meet with good doctors and learn more, it will help him. Try not to judge.
Just try to imagine how scary and confusing it is to be him right now.
Su