Flu for 6 days, still have a fever fluct between 38-39.5C. Not improving much. Tight chest, mild cough. Could it still be pneumonia without bad cough?
Possible. Did you have influenza diagnosed with a flu test or are you just assuming from symptoms; By 6 days you should start to feel better eventhough cough can hang on for 2 weeks or so. Pneumonia can be a complication of influenza. You should be seen especially if you were not seen initially for these symptoms.
Unlikely, but. Pneumonia as a complication of influenza is less likely in a young heathy adult, as compared to those over age 65 and people with a chronic medical condition. Although most people feel better in a week, some will be symptomatic for 2 weeks. Though less likely it's best to call your doctor for advice.