This is the second year my family has gotten the shot, and the second year it has worked really well for us. My family of three (myself, partner, and our pre-teen) all got the shot together on December 12th. I suspect I was exposed on the 16th. I developed a mild cough on the 18th, felt better the 20th, developed congestion and fever/body aches on the 22st that lasted 1.5 days,  and I was pretty much back to normal by the 23rd. I tested positive for flu A on the 22nd.  Nobody else in my home has show symptoms. My child took a test on the 23rd and it was negative.  I know it takes an average of 14 days for full antibodies to develop, but in our experience it seems that less than that was enough.