To get an absence note for school/work? To make sure it's a common cold?

For a cold, just wait a week or two. There's nothing medicine can do for you anyway. If it's still there, then it's worth checking. Also, you shouldn't need a sick note unless you are off for more than a week (your legislative framework may vary).

It depends entirely on the employer. Some places will require a doctors note if you miss more than two shifts. So in places like that, people typically go to work sick, and just spread the disease. This includes most fast food restaurants so think about the implications of that.

Still, it's their fault for not seizing political power and installing a better legislative framework.

Wait a week or two? That's what they told to my father in the military some 40 years ago. He's still fighting the consequences of that pneumonia.

I wondered the same thing. My mother was a registered nurse who rarely ever took us to a Dr unless we were very sick for several days. For colds she simply treated the symptoms. If we had a fever it meant bed rest and sipping 7-Up to help settle the stomach. The only time she took me was for ear infections and tonsillitis.