Feeling Feverish and Exhausted,

The past three days I have been having cold chills and then hot flashes(I've never had hot flashes before but from what I've been told that's what they probably are lol) slight body aches but not severe. I'm completely exhausted. Just feel like I've been hit by a bus. Was tested for Covid three times and flu once. Not sure if this could be something viral. Has anyone had anything like this a week before period?

Thanks in advance!

Edit: Throughout I've been taking my temp and the highest it has been was 99.1.

I feel like I have a fever. But do not.