It is always a good idea to visit your dentist regularly.
There may also be reasons why you shouldn’t get teeth whitening, and a professional dentist will be able to spot this.
You may also want to ask your dentist about a “De-scale and Polish” service. This will usually improve the appearance of your teeth to a certain degree.
You can also ask your dentist about tooth whitening. They will be able to advise you, and will usually offer a teeth whitening service.