Basically, you want an excuse to stay home next week? Do you live with your parents and are trying to get out of school? If so, simple. You are really sick tomorrow. You don't do anything but stay in bed because you (don't) want to get better. Then Sunday (evening is even better), you are feeling better. Good enough to do something. But you over do it and have a backset. You are up most of the night sick. You make sure you are up long enough where you get minimal sleep and really need to get rest Monday. Tuesday, you are feeling a little better, but not enough to do anything yet. Wednesday, you go to school (or whatever it is you were trying to get out of), but you still don't feel good, so your teachers don't see that you feel like garbage and don't expect too much out of you.

If you want to add another day, on Tuesday, you announce that you actually feel worse than you did on Monday or anytime over the weekend. Then you don't have to go back until Thursday. A real cool cat can get out of it until Friday. But in my house, there was a rule. If you are too sick for school on Friday, you were too sick to do anything that weekend. So I always was able to make it on Friday, even if I was really to sick to go.