Was my son misdiagnosed?

friday my 7 year old son came home from school with a bad headache and a fever. this is sunday morning and he has had a fever ever since friday afternoon, but I keep it under control with ibuprofen about every 7 hours. he's been up playing like normal, not sleeping during the day or anything. no sore throat and no body aches. a slight cough and slight stuffy nose. I took him to the saturday clinic yesterday and she diagnosed him with swine flu. no test was done. my question is, do you think he was misdiagnosed? or could he have swine and just a mild case. again, symptoms are this: continuous fever, slight cough, slight stuffy nose, had headache first day. he is acting completely normal as far as up and playing all day. I should add that thursday afternoon he got the seasonal flu shot-not sure if that has anything to do with this or not. any advice is helpful!