Swollen feeling & 1 slightly swollen tonsil on left side of jaw since jan. dr's blood tests & ct scan are normal. no feeling of large lymph nodes or infection. is there something that tonsil could be?

Localized: a single swollen tonsil may be due to a non infectious issue. Suggest ENT referral

Biopsy: If the tonsil is truly enlarged and is causing symptoms it can be due to infection, the presence of a squamous Ca lesion or lymphoma. A H&N exam can easily tell the difference in appearance between the normal tonsil and the enlarged one and at that time a recommendation of bx or not would be made. Blood tests and CT scan frequently do not detect suspicious changes.