If you think you have brain damage get an mri scan done on your brain.

If that shows nothing have a neuro psychology test done.

Sometimes our brain hard wires itself to do things because of a subconcious state.
This can affect our motor skills.

Try to get yourself tested to rule things in or our. Please talk to a professional about your concerns.

Sometimes we can be born with brain deficits. Sorry Infinitesadness not sure if you posted something prior to this that might link into this post.