Implantation?

[asteri]

So, this morning I get up and go to the loo and there is a teeny tiny spot of blood on the tissue literally the size of a pinhead maybe a teeny bit bigger, but it was like a pinky brown colour, I am currently 8DPO on a 28 day cycle and AF isnt due until Monday, could this be implantation bleeding and if so, how soon after can I test?

I got a +ve test 10 dpo

had a small smear of blood on tissue, 5 days after ovulation, so try in 5 days time

Thanks