2 questions in 1

I don't have cycles unless medicated. This is the first cycle that I induced ovulation. Af is due today/tomorrow based on apps if I had normal cycle. I tested this am bfn. This evening when I wiped there was some brown blood/specs in cm. So...

1. It could be af. Have any of you ladies had a cycle start on its own after 1 round of medicated cycle?

2. Holding out hope it somehow could be late implantation bleeding. Anyone had late implantation bleeding or know if it's possible?