Has anyone experienced this on minipill?

Hello ladies,

I am 3 weeks into the minipill and have been using secondary protection except when the condom broke (we got a new one right away). Yesterday was my day of ovulation based on the calendar I use since I got my period back. It’s been about two weeks since the first day of my period and I started having some bleeding that’s both red, pink and brown. I’m worried that it’s implantation bleeding. I did take a pregnancy test and it was negative but planning on taking about one. But seeing if anyone experienced breakthrough bleeding on the minipill.

Thank you!