Weirdest period ever

So I missed my period for 15 days all test up until day 10 was negative so I assumed I wasn't pregnant then on day 16 started spotting so I assumed AF came but its been 3 days and its just light spotting accompanied by the occasional killer cramps that make me pause whatever I am doing now back to the weird bleeding it doesn't come out on the pad but If I insert the tampon its there I have headaches before the spotting I was vomiting when I ate sore boobs frequent urination back aches always tired have no idea what's going on with my body anyone ever went through this