Tinnitus is not technically an illness or kind of illness connected to your ear or any associated processes. To be more precise what has taken place is there typically has been some sort of physical damage caused by something. Something has taken place, either a one-time event or recurring exposure to loud noise. Continual exposure to loud noise at your job, and you are not wearing hearing protection can cause tinnitus. There can exist instances in which particular other medical issue has produced ringing in your ears. If your disorder evolved over time, then that can make it hard to pinpoint the exact cause. If this is something that causes you distress, then the best line of action is visiting your family physician.