Low grade fever- early pregnancy?

I've had a low grade fever (99°F-99.6°F) for several days. It started when I was about 8 DPO and now I'm 14 DPO. I've also been charting my BBT and it's been consistently higher than normal too (98.8°F-99.3°F). 
Did anyone else notice an elevated temp before a BFP?
I tested yesterday and it was negative. Testing again in a few days.