Possible implantation bleeding?

I was ovulating when fiance and I BD on the 15th, been having random spouts of dizzynes, heartburn followed by nausea, headaches as well as recently noticing my being very tender. Last night I went to the bathroom, wiped had a little bit of brown blood (tmi, I know) put on a pad and just a few more brownish blood smears on it. My question is when should I test? I have very irregular cycles, so it's hard to know if I missed one. I'm coming up on 14DPO and wondering if it's too soon to test. Thanks!!