Most cases of tinnitus do go away on it's own eventually but it can take months to even years in some cases for the tinnitus to go away on it's own depending on how severe the tinnitus is.
If the tinnitus lasts longer than a few months or it gets louder or worse then you should see a doctor for treatment.
There's no actual cure for tinnitus but some treatments that the doctor can do can help with the tinnitus and prevent it from getting louder and worse.
If tinnitus is left untreated then it might lead to permanent hearing loss overtime but that's rare but still it's a good idea to see a doctor about it so they can help you manage the tinnitus.