While playing a PC game I suddenly got a light headache with some pain around my eyes.
Then later on I developed tiredness.

If this is the flu, what do I do against it?
I dont want to be sick.

And if it is the flu, how do I know if it is deadly? My mom has told me about a young doctor who got the flu and nearly died of it.

How do I know if I have the flu and if it is something that can be dangerous?