Ovulation bleeding?

Can someone help me please?

My so & I had vaginal & anal sex on Saturday. July 25. During normal sex, he let me finish & pulled out. We thought we used protection but what we were using slipped out of me.(come to realize that we actually didn't have any protection whatsoever) After that we proceeded to do anal & he finished inside of my butt & after that, I went to the bathroom to clean myself.

Now today being the 28th, yesterday as soon as I woke up I noticed bleeding. I wiped & it was stringy & brownish red. Im pretty positive that it isn't my period because my last one was July 16 to the 21st. I want to say that it's old blood but does old blood come out after a week? I'm confused...

Also I told my hubby & I decided to research it & all that came up were "ovulation bleeding" & "implantation bleeding". Its is quite a lot of blood. I'm not on any oral contraceptives or have an IUD.

I want to test, but I also want to know what is coming out of me. Can someone help me please?

Anything is greatly appreciated😊