Ovulation.. or implantation?

Ashley • 25, married to an amazing man, i have a step daughter and we have a daughter together. Born Feb 21st ❤ Natalie joy ❤😍 trying and praying for baby #2 🙏

I got a positive opk on the 15th. The 16th being the predicted ovulation day, which if it went like that I'd only be 3 dpo. I got a bit of pinkish spotting today at 3:20 pm. I'm just kinda wondering what it could be.. later ovulation maybe? I think it's too early for implantation bleeding