Get to an ENT guy ASAP (which you are doing) do not wait - and get a biopsy. No more antibiotics. Insist on a biopsy. Particularly of the tonsil - but if they can take a piece of one of the bad ulcers that would be good to. (he said your tongue was normal because it was on both sides? seriously?)
If your biopsy comes back positive for cancer then make sure you get a referral to a cancer center (hopefully you have one locally) Someone here has a list of the top CCCs and will probably post it for you. A local hospital can probably perform the surgery required but depending on the type of cancer and location of the primary the treatment may be chemo and radiation. Its best to go to a cancer hospital that deals with your type of cancer.

After a positive biopsy - the next step is a CT scan, MRI, and or PET scan depending on your doctor. This is to see if it has spread.

However this is all an IF - try to relax until you get the results of the biopsy. I know it's terrifying to face this but this is a great place to be if you hear the bad news. A lot of people here have amazing advice, and support to offer.

Best of luck to you. and take care.