61 days and counting

I'm currently 61 days late. My last period was in January and it was for one day. I had sex back in December but I had just had the depo shot for a little over a couple of weeks at the time. 2 weeks before I had the shot I took a plan b and I'm concerned it might have affected the shot. I've taken pregnancy tests and they came back negative. I had been feeling really nauseous since January. It's only really now that the feeling of nausea has started to lack down. My breast have been sore and my nipples are sensitive. And lately I've been having a lot of diarrhea (sorry, tmi). And usually I don't have diarrhea unless I'm sick. I've also been dizzy on and off. I've felt some fluttering in my stomach. And now it feels weird when I lie down on my stomach. Then I see this about cryptic pregnancies: