In your case, a diagnosis of cancer is very very highly improbable. I mean how common is cancer of the tonsils anyway?!
Briefly, this is most likely a viral tonsillitis ; the pain radiating to the ear may be due to an associated left middle ear inflammation (otitis media), or because of the vicinity of the nerves that pass through the area, the radiating pain exists. Worst case scenario, this could be a bacterial tonsillitis, and can be treated with antibiotics.
You need to have a doctor examine your throat, sinuses and ears, and take a swab culture from your tonsils (to see if it grows bacteria). He/she will decide whether there's a need to start a course of antibiotics.