Dude i dont ever get flu shots because that shot all it does is weaken your immune system and well leaves you weak as hell so when you do catch the cold or flu youll get it even worse and longer because your immune system was weak from the flu shot.
My opinion dont get it its not worth it, trust me.
Btw im a student at UTB University,at Tx Brownsville and im currently studying to be a pathologist and i kinda know my stuff about this and research shows that it does not help at all and it even shows that it weakens it more especially if you work out, your body cant mend it torn fibers from the daily exercise you put it through and combat a flu shot at the same time so your pretty much gonna get real sick after you take the shot.
And only companies advertise that its a good thing because they dont care if you get sick or not, all they care about is you buying more shots so they make more money.