My throat feels sore already 3 weeks and have ulcers on the tongue?

Apparent viral ulcer: The ulcers could be herpes simplex(1) or coxsackievirus group a. In either case it should be self-limiting unless there is some under-lying immune dysfunction or immune suppression. Aphthous ulcers are more usually in the buccal mucosa.

Can be viral....: Many viral infections mimic bacterial and only your physician can look for other signs and symptoms and help you out!