late period.. confused

El

my last period was September 20th. My next period was due around mid/late october and its now November 6th and I still havent gotten my period. ive had all the pms symptoms.. bloating, acne, cravings, tired, sore boobs. Took some tests but they are no where near being a positive. Just confused on what could be going on? im not atressed out in life at the moment so stress isnt stalling it. Any ideas?