My Period Was 5 Days Late, When It Appeared It

My period was 5 days late, when it appeared it lasted for only 2 days, i had no usual signs of my period arriving and it stopped abruptly after 48hours. Im now starting to have mild cramps in my abdomen and hot flashes to the point where i am sweating alot and nausea. I feel constantly bloated and tired. I am not on any birth control either. Do you have any answers to what could be causing this? The "period" was a normal bleed for 1 day then like a brown discharge the 2nd