Brown spotting

Adriana

I've been having cramps since last night and into today , I've also been spotting brown mucus stuff. Its 4 day until AF , I'm never early! Took a test this morning and got a BFN , could this be implantation spotting? When should I test again ? BtW this month was my first round of

<a href="https://glowing.com/glow-fertility-program">IUI</a>