Will tongue swelling kill me if I don't get treatment?

It can. When tongue swelling is severe, it can block the airway and make it very difficult to breath. There are many causes of swelling and I would recommend discussion and evaluation by your doctor.
Severe + progressive. Can kill you if an allergic reaction causing severe tongue swelling. This can restrict ability to breathe and thus an emergency. Simple distal tongue swellings are not serious.