Bfp but light bleeding since ovulation

Bryony

HELP! I’m due to come on tomorrow but I’ve been lightly bleeding for about 8 days - enough to wear a thin panty liner, and weirdly only in the mornings. I get waves of light cramps but they never come to anything. I took a test today and it’s positive - do you think this will be a chemical? Has anyone had bleeding before and after BFP?