Needing some advice!!

Okay ladies I’m needing some help. In the month of January i had sex on my ovulation days, but then later received my period as usual. In that same month about a day after my period ended i had to have surgery. It is now February 20th and I’m 8 days late with major swelling and tenderness to my boobs. I took an HCG test later in the afternoon and it said negative, but yet still no period and still major swelling in the boobs. Does my surgery have something to do with such lateness in my period or should i take another test?