So according to the app my period is 5 days away. I have been spotting for 2 days now.. light pink blood every time I wipe & some little drops in the water. My husband and I have been having unprotected sex (withdrawal method every time) over the past month since my last period. Generally, the app is either always correct about my period dates or one day off. However, I do not usually have any spotting before my period. Along with spotting I'm cramping but not quite as harshly as during my cycle (which is usually a 10/10 pain level.) So I took a pregnancy test 2 days ago when the spotting first began (6 days before expected period) and it was negative. When should I test again? Is this implantation bleeding?

Also, I seem to be producing colostrum in one breast. But I did bf my child until 18 months (she is now 2.5) so I may have milk not completely dried up.