If you're two days late, and still have high temps, I would test! When it comes to temperatures, what's "normal" when can differ quite a bit from person to person, but if you're pregnant, your temperatures will stay above your coverline throughout the pregnancy. They say 18+ days of high temps probably means your pregnant!!!
Best of luck!
If you are pregnant, your temp should be in the range of 98+ for entire pregnancy. i suggest you to test for peace of mind.
good luck