I think Debbie and Sally are right. Spasticity can be the cause of feeling like you have shin splints. I have experienced that myself and know full well that I didn't do anything to cause the feeling of shin splints. You could be having muscle spasms. Not all spasms are painful.

BTW - I was a runner too! I dream of the day I can do it again as I love the feeling I get while running. I know the dream more than likely not become a reality but it's nice to think about.