You need to discuss how you feel with a medical professional, you might need an antidepressant. I have PCS and the turning point was the prescription of Cymbalta (antidepressant) for me, it has lifted my mood, relieved the pain, helped me sleep and now I am on the mend. PCS is very difficult to deal with and it is important that your mood is stable in order that you get better, if your mood is low/flat I think it makes symptoms persist or worsen. I wish you all the best, but you need to talk to a doctor or another health professional face to face soon.