That was just a random quote I remember from school. XDWhoa, doses? It's a single pill, LOL. Also his pain apparently wasn't just a little, and he needed his concetration to his max to study. I don't understand him.
Even if your friend took a pill, the reason why he has a headache would still be there and I have a good feeling his pain would be soon back anyway (pills have a limited time to work, and with sharper pain the time tends to be shorter than usual). A worn out mind and body don't sound like a good base for studying, you can plant seeds but still need a good ground to get results.