Stumped about pregnancy...

I have been a little stumped … November 25 I should have started my period… I was a little late, I started October 7th but it was just brown then the next day it was pinkish blood for half the day. I always have my period 4-5 days, but only had it for a day in a half two… I went in for a blood test and it came out negative… it is now December 10 th no period and for the past week my breasts are swollen they hurt and my nipples hurt… they are kind of full and heavy, I don’t know how to explain it… what do you guys think. I have been very tired the last week as well, like I haven’t slept at all… 2 hours after waking up I am ready for bed again… This is a hard subject to talk to my husband about because he got a vasectomy about a year and a half ago… I am so stumped??? Any help?? And just so you all know, I would never cheat on my husband nor have I ever… Any help would be greatly appreciated!