Headaches and spotting

Ashley • Been with my husband 12 years, but married Aug. 2015 :: we have two daughters 💗💗 :: TTC #3
For the past 3 days (not today) I've had an on and off slight headache.. Which I never get a headache. I've also had slight spotting of light pink/brown. AF isn't due til January 10th. I took a HPT this morning but it was negative. Too early to test? What's going on??