Does it hurt a lot when getting a scaling? I'm wondering if I have to do it every year.

I am so afraid of the dentist that I haven't had a scaling done even once in several years.
My gums have been bleeding occasionally lately, so I'm planning to go see a doctor, but I'm really scared that the pain might be severe.
There are many reviews saying the sound is scary and it makes teeth very sensitive, so I can't bring myself to try it right away.
Please let me know if the pain is really bearable and if it is absolutely mandatory to get it done at least once a year.
If you have any tips on how to overcome dental phobia and receive treatment comfortably, please be sure to share them.