I am in a concussion...very very long.?

You should not be in gym. So concussions can take over 2 years so heal. Just hang in there. The reason you do not want to do gym is because you do no want to take a chance with Second Impact Syndrom. This is when you get another concussion before the other one is healed. Because there is already swelling in the brain there is no room for more. Not to scare you but this can result in perment damage or even death.