FIVE DAYS LATE.. BFN??

09/22 I spotted for I feel like an hour because when I noticed the blood first time I’m thinking okay my cycle is coming ( supposed to come 09/24) but nothing after that.. I wiped yesterday 09/28 and I’ve seen blood and put on a panty liner. Throughout the day nothing was on the liner or when I wiped. This morning I wiped myself and the tissue was brown ( thinking from yesterday’s blood?) then I have taken three cheapies and all came back negative. What gives?! This has never happened before and my cycles are regular. Has this happened to anyone before?