Just starting Thursday I had some really light bleeding on my pad, which looked just like implantation bleeding and it was right when my period was due. It was so faint and only lasted a couple of hours, I also have been having stomach cramps, headaches, backaches and occasionally sore boobs like mild shooting pains in my boobs, I also have felt very tired and just on Friday I could barely move because my muscles were aching that much, and I keep getting weird sensations in my stomach, I took a test on Saturday and was convinced it was going to say positive but it was a negative, could I still be pregnant and I took the test too early? I have missed some pills and not been using condoms recently