Help please

So i have irregular cycle i ovulate an 3 of aug i spotted at 8 dpo could that be implantation spotting just two pinkish stopping last for couple mins???? I took a test at 9 dpo bfn an took one yesterday bfn again...is there a chance i could still be pregnant?? AF is due next week saturday...i tests i took wasn't fmu..my back hurts someone.an sometime i get tired an nauseous an really hungry.....