Hey guys I’m scared and need help someone please calm me down

So idk how to count pregnancy I’m young but the condom broke and we rushed to get a plan b. And it’s been like two weeks since but I’ve been reading that you don’t have symptoms (spotting) at two weeks Nd if u do it means ur 4 weeks pregnant but that’s the only time cum actually entered my body so I don’t know. My period was supposed to start three days ago I took a test yesterday and it said not pregnant please someone respond😭