Aunt Flow or Implantation

Soo I had sex with my SO on 31st of March. It was our highest chance of getting pregnant 33%. It is either 10 or 11 dpo and for the last two days i have been spotting but it is not enough to fill a liner and its brown discharge. I have been getting nausous and cramping and my breasts are tender and I've been really moody. My flow is normaly on time sometimes 1 or 2 days early but never a week. Is it possible Im pregnant or just anut flow coming early. I'm not sure when or how early i should test. According to glow my period shouldnt start for another 5 days.