3 days light pink & brown spotting TMI

Jessica

I am SOOO confused!!! So for the past 3 days I have had VERY light spotting. My temps have also been up and down. It started out pink and today it was brown & I'm 13 dpo. I have mild usually one sided cramping associated with it & it seems to only come out when I go number 2 (pushing.) It's not showing up in my panties only when I wipe. All pregnancy tests have been negative so I'm not sure what's going on....