Implantation bleeding?

I've been ttc for 2.5 years without any luck so im not expecting any luck this month but still thought I'd ask for your thoughts...

my cycle is usually 27 days, on the odd Ocassion it has come one or two days early or late. However last month I was 5 days late for the first time ever. I decide this month to try using a digital ovulation test and tested from day 9 till day 16 with no smily. On day 18 I had a couple of spots of pinkish blood and some after bding. Day 19 there was nothing and then today (day 20) nothing again apart from some pink when I wiped after bding again.

My gut feeling is that I probably ovulated early this month and therefore AF is on its way early psrticulstly as the ovulation test showed nothing but part of me still can't help praying its implantation.

whats everyones honest thoughts and why all of a sudden have my periods gone like this?

thanks x