Is it illegal to get fired for missing work because of surgery?

I am getting my wisdom teeth removed and am scheduled to work 2 days later, my boss said I am required to come in and have to come in or I would be fired even with a doctors note, even though my face would be swollen, I would be on pain pills, and barely even able to talk. Is it illegal to fire someone over th
Update: if it is illegal, what can I do?
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