Where is my period!! I’m freaking out

So I took a Plan B on 10/6 after having unprotected sex earlier that day, I took it just in case. After I took it I experienced super tender boobs for like 2 weeks but no other period symptoms, my period never came. I am now 27 days late and still no signs of my usual period symptoms, and I have no signs of pregnancy. When I tested, it came back negative. Where’s my period?? This is freaking me out!?

(P.S.) that wasn’t my first time taking a plan b (no judgement please) so I’ve definitely read the pamphlet that comes with it but I’ve just never experienced this before.