Implantation Bleeding??

Hello, I am on CD 16 right now. I am on the nose w/ a 28 day cycle always. I suspected that I ovulated early on CD 9 or 10 b/c I got a kind of positive on my OPKs. I started cramping around CD 14 and had a little pink spotting on CD 15. It literally looked like someone blotted a red pen a couple of times on the wet tissue. I have had a gradual darkening on my OPKs. Just took one and it looks sort of positive to me. I have heard that OPKs can sometimes predict pregnancy too. I have been charting my BBT too and the temps are rising, showing either I have already ovulated or I could be pregnant. I am so confused lol. I am wondering if I ovulated early and am having implantation bleeding b/c last month I had, what I think was, ovulation bleeding and it was a lot... very noticeable, like I was starting my period early. My breasts have started to get more and more tender and I've been having a little nausea and loss of appetite. Gosh... I'm so confused lol I know when you are TTC, you start noticing every little sign. I've never had mid cycle bleeding until last month so I'm WAY confused. Anyone had this before? Any advice would be helpful! THANKS! LOBD!