What Causes Delayed Periods Along With Sore Breasts And Nausea?

Hello, I had unprotected sex exactly one month ago (6th) and also two weeks before that and he ejaculated in me both times. The next day (7th) I had my period. My cycle is usually 40-45 days. I have sore breasts, feel nauseous and am very emotional. I got a negative pregnancy test 5 days ago (1st). I m not sure when I would get an accurate result?