Man, a 70 hour week! No wonder you're having trouble remembering things and concentrating. I don't think you'll find any answers. Science just isn't advanced enough to tell you why these things are happening and even if it was, unlikely that the docs could do much about it. From the little research I've done following my injury 6 months ago I've found out that there don't seem to be any fast rules with brains. I did notice however that a brain can be working harder after a concussion for up to 7 years so it's a good idea to take it easy when things start to get too much even after 3. My injury was a relatively mild one which made me confused for 15 minutes but I still have problems with concentration and my short term memory isn't what it used to be. I however suffered acute anxiety and depersonalisation, the dp from which I am still recovering from may account for some or all of this, again, noone knows, so you and I just have to be positive and find ways to live with it. Sounds like you're doing ok though if you can work hours like that and are in full time study. My guess is that in a few more years your problems will be history, if not sooner.