Conceive question

I had my period from 11/11 - 11/15 so on Friday night while Black Friday shopping I was having some mild cramping. I went to the bathroom because I have irregular periods to check and there was a small amount of dark reddish brown blood. It was in my panties and when I wiped. I watched it for the rest of the night and nothing else came out but still have the cramps. Still to this day nothing else, my question could that have been IB? I go to the gyno tomorrow for a check up on a cyst and want to wait for a test but knows it will be negative jus rather get told that way! Any advice ladies..