I'm being treated for a sinus infection, an ear infection, and tonsillitis with amoxicillin. My symptoms seem worse now (after 5 days) is this normal?

Try another drug. Although Amoxicillin is an "okay" drug, it is not one that i ever prescribe for a sinus infection. There is a lot of resistance to it in the community. It sounds to me as if you might do well with a change to a stronger antibiotic. Contact your doctor and tell them that you are no better and perhaps they will be able to switch you to something else.
Contact Ur PCP. Your present sx may indicate the germ or germs involved are resistant to the antibiotic you are taking. Contact your pcp discuss your sx. A followup or change in med is in order.