i ovulated the 10th of August and didn't have sex the whole time I was ovulating. I had sex August 26 half of the time with a condom and the other half without but he did cm inside a comdom and when he felt like he was going to cm we stopped. My period was suppose to start August 31st but started September 1st. My period is really light it's like brown red and pink. I'm also cramping like my regular period. But the flow isn't normal I'm concerned so is this implantation bleeding or no?