Not sure wether to me happy or worried :/

Hi all 
New to this - eeek! So I am 9 DPO and yesterday evening after having sex and climaxing (sorry tmi) I had a slight bleed literally when I wiped only and stopped after 20 minutes approx.  Today I have lower abdomen cramps... So I was wondering if it was implantation..? AF due in 6 days. Little concerned that I bled after sex though... There was no pain just the bloody discharge as described. Am I right too worry or could it have been something? Thanks for advice guys