HELP PLEASE!!!! NO PERIOD TODAY !!! SPOT OF BLOOD TODAY!!

So,today I'm due on.. had a pad in all day nothing,just went for a wee,nothing in pad tiny spot of blood when I wiped so I wiped again & nothing? I've not had backache/cramps like I usually get before period,just been feeling sick..so I've taken a test & negative. What could that spot of blood be?? I'm really unsure I thought oh maybe I'm gonna come on,but surely there would be more there when I wiped the second time? I'm after a bit of advice reall has any one got there BFP after testing the day they missed a period? Could it be IB? Or am I too late for that??!! I really need some more advice,or maybe a bit of hope. I'm scared I'm not..but worried there may be something wrong. I currently have a cyst on my ovarie too