Help with possible ib. No graphic photos only my chart..

Heather • Mommy of 💙💓💓💓💓👼👼
OK so I'm only 6dpo today and I have never experienced IB before. This of course may not be IB. So I went to the gym came home to take a shower and there is brown cm in my underwear. Only a few spots. Af is not due until April 2nd. There is absolutely nothing when I wipe. And it would have only lasted a few minutes.. Could that be IB?