Fever while pregnant

Caitlyne • Bonus mom to 2💜💙 Bio mom to 1 💜
My SO managed to get me sick... It seems to be hitting full force today **knock on wood** 
I've got a mild stuffy nose (which I've had most of the first trimester, but gets worse at night now that I'm sick) 
Really bad nausea, I haven't physically thrown up yet, but I think that's partially because I have a fear of vomit. 
I've got a fever at 37.9 Celsius (100.22 Fahrenheit) 
And lower back is aching badly just to lay here no matter what position I move to. 
Of course I've got the usual body ache too. 
& a manageable headache. 
In 13 weeks, and just wanna know when I should call a doctor or go to the hospital when it comes to my fever. 
It's slowly been rising, was relatively normal this morning when I woke up at 3am. 
And if any of you have any natural ways to help with everything I'm open to suggestions!! 
Already took some acetaminophen earlier a couple times but don't want to take anymore.