Is this a legitimate excuse for missing an exam? The class I am teaching had a quiz yesterday. A student wrote to me 2 hours after  that he missed the quiz because he suspected he had a strep throat. He would see doctor and provide me a doctor's note.  Personally I feel this particular reason is a little lame. If he decided to skip the exam because he suspected he was really sick, he would have wrote to me earlier. My question is, if in the end the doctor says he did not have strep throat, should I still give the student a chance to make up the quiz (just because he suspected it)?
Rather than having to think about what is a legitimate excuse or not, I routinely give make-ups to anyone who misses a quiz or exam. Yes, it is explicitly assumed that they are operating with knowledge of what was on the quiz or exam that was given, so the situation is somewhat different, and the nature of the make-up is consequently somewhat different. I explain this at the beginning of the course. One might worry that there'd be too many people trying to game the system, but it seemed not so.

(I think it is not reasonable to demand that people who are sick get a note from their doctor... if it's something like a severe cold, say, because the wisest and most socially reasonable thing to do is stay home in bed, not travel to a clinic... Also, I do like to cultivate the atmosphere that I am willing to believe students' excuses, rather than have the default be skepticism about their honesty.)