Hi there Mari3.
If your doctor suggested that that lump is a lipoma, you can breathe a little bit easier. What it is, is just a localized collection of fat under the skin. Usually it's soft, which is in contradiction to a cancerous tumour which are usually hard, and immobile.
The ENT guy will do a head and neck exam, feeling all of your lymph nodes in the area (there are a ton of them), he'll look down your throat with a mirror (indirect laryngoscopy). It's pretty easy to tell if something is a lipoma, so there probably won't be too much involved in your appointment.