Am i pregnant

Hi i was wondering if someone can please help me im at a loss. I came off the pill in January 2018 and my periods have  pretty regular, middle of every month, the last 2 periods (may/June) I had brown discharge for like a week before my period which would last around 6 days. 

My partner and I had intercourse around a week before my period was due, I had light spotting for a day after then thick white discharge for a week instead of my due period. Then this turned into stringy yellow discharge, then now (3 weeks post intercourse) it’s brown. I’m having dull cramping (which ive never gotten with the brown discharge), lower back pain, little more hunger, breakout. Took a hpt and it was negative, have no idea what is going on? Sorry for the long message please help

thank you