Pregnant ?

Hey guys! I’m in serious need of advice right now. My boyfriend and I had sex two times last week, the 17th and 18th I believe, he didn’t cum in me but I’m sure there was Precum, I did take a plan b the day after. I thought I got my period two days ago but it seems super light to be my period so I researched it bc I overthink too much and I saw something about implantation spotting which scared me but I also read that plan b can cause spotting as well so I’m very confused. The picture is my calendar for my period... someone please help me calm down 😭