full week of brown blood (not period)

this all started about a week ago when i entered my fertile week and it is still happening. it’s never happened to me before and i don’t know what is going on. started with a light brown blood and then got darker and darker even red at some points. sometimes there’s small clots too. i just started working out again (weight lifting) and it seemed to start after i started that? related? it’s not like a period, it’s like a discharge amount and comes out randomly. i took a test a few days ago and it was negative and the app says my period is due in 9 days. anybody had any similar experiences or know what this could be caused by ?