Can implantation happen at 5 dpo?

I am cd 17 today and 5 dpo aprox, i had a tiny blob of clear cm this morning with a red streak in it, but now when i wiped, the loo paper was a good shade of pink.

Last cycle i had pre O spotting for 3 days at cd20 then i Od on cd24.

I believe i Od on cd12 this cycle as i had ewcm on cd12, cm on cd13 cramping on cd14 and 15, mild cramping cd16 and today cd17.
We only dtd on cd11 in the evening and cd13 really early in the morning.
Af was on feb 10.

Has anybody had implantation spotting on 5 dpo?
Could af be showing up early?
Could i have not Od when i thought and this is now pre O spotting?

Any advice, comments, stories ARE VERY WELCOME.

TIA.