Sounds more like covid than flu. Flu almost always has a high fever and sinus pressure is rare. Covid is know for sinus pressure and fever is not always observed.

Get a test if you want to know.

There is some reports of a covid rash. The rash also might be unrelated and some sort of allergic reaction.

Measles has a high fever usually. Chicken Pox is very itchy.

No one here can really guess what you have.

Stay away from others, wear a mask. Call your doctor and/or get a covid test. Whether you are positive or negative for covid you need to treat your rash probably.

I am sorry to have to say this User1234 but this question should not be asked on a general question and answer site because it is doubtful that any subscriber can give you a proper answer.

Even if there are qualified medics or doctors here they still would not be able to diagnose you without an examination an/or tests.

You must agree that the sensible thing to do is to contact your surgery and get a proper diagnosis and treatment.

You don’t know but it may be contagious but please don’t fret about it being Covid until or unless it is diagnosed by a doctor.

Good luck