Bleeding at 6DPO Period? Implantation?

[Rainstorm]

HI ladies, I'm writing cos I'm very confused. I had my LO 13+ months ago, and since I EBFd till 6 months, and then continued nursing him to sleep and confort feeding, I never got my period back. We have been NTNP, which is TTC but without much hope since it became evident after 6months no period that BF worked quite well as a contraceptive in my case.
Anyways, one day I get some mild pain in an ovary, so I start paying attention, assuming it could be ovulation (this made sense cos I spent 12 hours without nursing one day the previous week, and I read that kind of change in routine may be enough for period to return). We had sex on the day of alleged ovulation (by chance), so I started tracking down symptoms. On -supposed- 6DPO (yesterday) I started bleeding. I was very surprised and shocked cos it's been almost two years since my last period. I was disappointed but at the same time, I felt happy that I could start tracking my cycle and I was closer to getting pregnant again.
Then this morning I wake up: no blood, my pad is clean. nothing. I bled for less than 10 hours (bright red, then brown, then nothing). Could it be??? Sorry for the lenghty post

 

[mera.mera]

I guess it could be implantation .. good luck