brown blood mixed w discharge ?

i’m in my fertile week and i’ve been having brown blood come out. it started 4 days ago and it’s never a heavy amount it’s the amount that would come out as “discharge”. i was working and i felt something come out and i assumed it was discharge until i got home and saw it appeared to be a brownish blood. it seems to be mixed with my discharge and have the consistency of what my discharge should be. it’s still happening and i don’t understand what is going on. maybe ovulation bleeding? but i never have that. my CM is always white and healthy. or maybe it’s left over blood from my period 2 weeks ago. does anyone know why this could be happening? i’ve not had unprotected sex. all condoms have been good because i check them so i find it hard to believe it’s implantation bleeding, especially since i’m right now about to ovulate… i took a test and it was negative too.

i would also like to add i recently had a change in my lifestyle and i started lifting heavy again and i’m aware sometimes that can affect a woman’s cycle. i want to know your opinion because i’m confused on why it’s happening.