Mid cycle bleeding

Got a peak cycle day 15, cycle day 16 was still a positive but line was not as dark as 15 and came up as high. Cycle day 17 i stopped but then that evening i noticed blood. Been light bleeding for 4 days(first 2 red 2nd 2 brown) and had spotting today(brown). It its too early for period and implantation and too late for ovulation. Has anyone had this before?