not all viral infections are influenza so your self-diagnoses may have been incorrect. there are hundreds of different viruses that can cause flu-like symptoms. while the flu vaccine is not 100% protective (especially this year) it is possible to get another strain of influenza that is not covered by the vaccine. influenza viruses can mutate and shift after the vaccine has been made so the viruses occasionally are one step ahead of the cdc.
got flu shot then got what seems to be flu twice once in jan. then in march is that possible? . had fever 101 body aches sore throat runny nose.