PCOS pms or pregnancy symptoms??

I'm in the same boat as some others that i have read about but no one seems to get an answer. It's really upsetting because a) I'm all on my own going through this and b) I just have this feeling that I am but the test that i took first thing this morning was negative. I have sore boobs, a weird sensation in my lower abdomin, light headed even when laying down, super tired, mild cramping, heavy feeling down below, constant urination, headaches, funny taste in my mouth and restless sleep. Could all this really be a lead up to a period? Last period was October and had unprotected sex on the 23rd December. Four weeks ago today. Is it too soon to get a BFP?? Has anyone had a similar situation? Oh...and i have very irregular periods but i have been charting and my next one is due on 7th feb. its like a 4 month cycle. Whilst charting, the particular app that i use showed my ovulation dates and the date i had sex was a week after my highest fertility date. Sorry for waffling but its driving me insane!! Help guys, please!