Am i just getting sick or is this an ear infection?

this started last night & has just gotten worse. i'm feelng an ache (like when you have a cold & it hurts to touch anything) that started in & behind my ear, but i now feel it also in my neck, jaw & scalp, & only on the left side. i can't say i feel a "fullness" or "draining" in my ear, but every few minutes i get a sharp, stabbing pain. i've never had an ear infection before so i have no idea what it's like. i have a doc appoinment next week, i was just wondering if anyone might be able to shed a little light on this beforehand. i have some left over amoxicillin from a tooth infection 5 months ago, could that help? thanks for your time.