Your sinuses may show clear on an x-ray and the thumping they did on your cheek bones may feel hollow now, but it takes a while for the bacteria that originated from the virus in your sinuses to be completely gone, which is why you need to finish the antibiotics.

Also, if a couple of weeks go by and the sinus infection seems to come back, you will need to get back in to the doctor. Some take a few times around to get knocked out of your system. Amoxicillin is good but sometimes is not strong enough. Cephalexin is usually tried if Amoxicillin does not work (same antibiotic family, more powerful).

Good luck!

Lindaru ;)