Only problem is the dominant strain of flu this year isn’t covered in the current vaccine. Also, the vaccine doesn’t guarantee you won’t get the flu that it does cover, thuogh the claim is that it should be less severe should you contract it. So, yes, of course you can get the flu after you’ve had the shot. This year it happens to be a particularly virulent strain of the flu that isn’t covered; and it is killing healthy people in short periods of time (about 40 hours for an otherwise healthy 17 year old I heard about on the news last night).
Your chances of contracting the flu this year are the same shot or not.
Even in a year where the drug pushers get the strain right, your chances or contracting the flu are still close to the same, shot or not.