Disregard the Grade 1 rating of your other concussion. The specialists know that the Grading system did not have any meaning on the intensity of the injury.

I suggest that as soon as you start to feel any symptoms at work, try to take some time for quiet in a dark room. It does not help to push through concussion symptoms. It is far better to use them as a signal to stop and rest. You will recover faster if you do not try to push through.

My best to you.