brown to red to brown discharge

hi guys, i’m really confused rn bc this has never happened to me but since the 28th i’ve been having brown discharge that has turned to red then brown again. The same thing has happened the next day, according to my app i’m meant to start my period on the 27th but i felt as if i ovulated late so when i tracked that my app said ill start my period tomorrow, the 31st. is this normal? any help would be great