New here. Needing advice please!!!

I am currently due for my period on Dec 23rd.  I bought the clearview ovulation tests and when I got the smiley face we did what we needed to do and continued before and after the smiley face every 2-3 days. I have taken a first response pregnancy test today And it was negative.  Within the last 3 days I have felt nauseous, had cramping, had a stabbing type pain in my lower abdomen, have been fatigued, and am currently cramping and have seen some VERY light pinkish discharge every now and then?  With my first 2 pregnancies I never had any discoloration OR no cramping so I am at a loss??  Any advice would be greatly appreciated as I am going crazy over here!