I was searching and printing articles on the internet in the afternoon. When about 10 minutes passed after I had started that work, I felt great pain in my head and had to quit. I went to my room and slept all afternoon. My work was postponed. In the late afternoon, I recovered a bit and returned to my lab. My senior come to me asked if I finished the search and print. The work was what he had orderd. No I said. Why? .....Because I..uh, had to go somewhere.. I didn't want to say I had a intense headache. But it seemed to hurt him my not doing the job. Maybe it would have been better if I had said about my pain. But sometimes it bothers me to explain such things How I ackes to somebody who doesn't have a much concern about it. To tell the truth, I don't want somebody's concern in case like this.