It appears that you are suffering from tinnitus. Tinnitus is an audible ringing noise perceived by the patient. Many cases of tinnitus are transient and resolves on its own. However, persistent tinnitus warrants medical testing. In your case, since you stated you had an accident resulting ni tinnitus, it appears that the root cause may be damage to the nerve endings of the inner ear. Other causes of tinnitus include aspirin overdose, Meniere’s syndrome, vascular abnormalities, or masses in the brain.
Evaluation for tinnitus should include a detailed physical and neurologic exam as well as auditory testing or MRIs of the brain if warranted.
Unfortunately, because tinnitus is a symptom with a wide range of etiologies, there is no one specific treatment. If an underlying cause can be detected by your primary care physician then (s)he can treat the cause. However, if the diagnosis remains unsolved, then referral to a neurologist or ENT doctor may be pursued for further evaluation.
For nerve damage causing tinnitus, some patients have found niacin supplementation to be helpful in reducing tinnitus. Others have reported positive effects by taking gabapentin (neurontin). However, neither of these treatments have any scientific evidence supporting their use and neither niacin nor gabapentin (neurontin) are FDA approved for treating tinnitus.