I think you're right about
the docs not counting it a fever until it's 100 or above. My temp starts out in the low 97's, sometimes dips into the 96's - but more often than not, it starts spiking up into the 99's in the afternoons, usually with some activity like chores, or cooking dinner.
But- it also at times climbs up even if I'm sitting still and reading, and other times exercise/activity doesn't seem to affect it at all, and I never get up to 98.6. Rheumy dismissed it as a conditioning issue - but it doesn't seem to correlate with activity. I do feel "feverish" if it's 99.5 or above, and I consider it a bit of a flare warning if it doesn't come back down into the 98's by bedtime.
A mystery - one I've considered posting about.....
At any rate, I would agree seeing the doc might be worthwhile at this point. Hope you feel better soon!