Just off the pill and confused...

I just stopped taking the pill in December 2018. AF happened exactly 28 days later. Now waiting on second true cycle on day 32 and very confused.

Yesterday took a pregnancy test (negative) and late today I have verrry faint brown spotting. Can’t tell if it’s AF or could it be implantation bleeding?

Can anyone tell when I ovulated based on my chart? Maybe just not enough info there yet... so much to learn!