My left front of my neck where carotid artery is spasms and hurts the carotid artery feels swollen and i think there's a knot.. i'm scared?

Torticollis: The Sternoclidomasoid" Muscle goes into spasm. I believe this what is happening to you. It is a benign condition. Nothing to worry about,although it is painful and cannot turn neck in all direction. Rx Anti Infalmmatory like Ibuprofen Ice application, Local Muscle recant like Bengay /Flexall/Deep heating and Oral Muscle Relaxant will help you. And if not better in 24 H. get examined by your MD.