Couple of questions - how old are you? And do you smoke ? If you are in your forties or above - then there's a possibility of HPV+ BOT cancer - the demographics is usually forties and up. If you are a heavy smoker it is also possible. Mind you usually this is a later in life situation - though not always.
There is also the possibility of thyroid cancer. A lump in the throat is always concerning. Though is could be benign or just swollen due to some etiology.
For a dr. To jump to cancer without scoping etc is more of a worse case scenario DX rather than an accurate one. It really could be anything.
For a dr, to say that he's basing it on personal information - your age, history health etc, basically you match a demographic - and present with a certain symptomology. But that doesn't mean he's right. Without a scope, and scans it only a guess. Please make sure the ENT they send you to is one familiar with oral cancer (not all are) and push to get in ASAP. Ask them to put you on a cancellation list. I'm not saying this because I beleive its cancer, but because its obviously causing major worry and disruption of your day to day life. Take care!