If you were cultured, they had to be looking for whatever is going on with you, not just that one thing. Sinus infections generally go away by themselves, and official guidance is not to use antibiotics to get rid of them because the use of antibiotics has been way overdone and is harmful to us in other ways as they don't just kill the bad guys, they also kill the good guys. So, by the way, does prednisone. So either your doc found something that had to be treated, or he just gave you something as a guess or to get you out of his hair. You need to ask your doc, okay, it wasn't that, so what was it? If you found nothing, why did you give me those meds? Also, a lot of sinus pressure isn't actually an infection, it's congestion that can be caused by any number of things, including allergies. Your doc is the person to ask this of, because that's who gave you such strong and potentially harmful medication that you will now have to recover from by taking probiotics, prebiotics, and taking especially good care of your immune system for awhile. If you get chronic sinus infections, by the way, one of the main causes of this is the use of antibiotics. Other things are mold or other environmental factors. You need to get a diagnosis, not a guess. Peace.
So you had a true sinus infection. ouch. Those are no fun. Glad the antibiotics are working. Truthfully, doctors rarely swab for exact pathogens and use a broad spectrum antibiotic to cover what 'most' people have causing the illness. Sounds like that's the case with you and you're covered. They'd swab if you weren't or if this hflu bacteria (whatever it is) is problematic in a different way and treated differently, so they need to know. But in looking at pathogens that ceftin covers, the Hflu is mentioned as covered. Not sure why they checked you specifically for that. https://emedicine.medscape.com/article/286227-medication That is an article on ceftin and the pathogens covered. Good old, streptococcus pneumonia is the most common pathogen to lead to sinusitis. https://www.cedars-sinai.org/health-library/diseases-and-conditions/a/acute-bacterial-rhinosinusitis-1.html I personally love this stuff. ha ha. The science behind getting infections. I have a son that has chronic allergies and when he gets ill, is prone to infections (much more so than my other son). I can almost always tell we are headed that way by the smell of his breath. Bad. We do use mucinex to think his secretions and since our ENT told us to do that, it's gotten less. Drinking extra water can also really help with thinning your mucus making it less likely to gunk up in the sinuses causing these unpleasant things.
Hope you are better by now!