Late AF but negative test?

My AF was due today but was a no show. I'm not crampy and definitely feel like she's not coming any time soon! I took a hpt but got a negative. I had what I thought might be implantation bleeding on the 16th, it only lasted a few hours and was SOO light. Definitely WAY to light a period. My period is regular and it's odd for it to be late. Have any of you ever had a negative hpt with a late period, but was actually pregnant? I have pictured below the spotting on Monday and the negative test in case some one sees something I don't! TIA