My first thought.. Make sure your neurologist is one that has had a great deal of experience with PCS and TBI! I didn't do that in the beginning and ended up wasting a great deal of time. Now that I have one who works with these types of injuries daily, he has been able to do a lot to improve how I'm feeling.

Second, I have realized and have been told by doctors that anything that brings on an onslaught of symptoms such as what you experienced in physics lab, means you are taxing your systems too much. From what I've been told, but it just my drs opinions is that this prolongs the recovery process. I don't know that it necessarily does damage? But it makes your recovery take longer.

Best to you- I've been on medical leave from grad school since March 2011. Hoping to attempt a return in January, but I worry that I will experience what you are.