When should you go to the ER for a sore throat?

I (26F) developed a sore throat yesterday. I’d been sneezing for approx a week, thinking I was getting a cold.

But oh my god. This sore throat appeared so suddenly and it is BRUTAL. It is kicking my ass. Yesterday I was able to eat some solid foods, I drank lots of tea with honey hoping it would pass. Boy was I wrong. It is currently 3am where I am. I have been awake all night with my sore throat and cough. I’ve gotten zero sleep. I’ve taken 3 cold and sinus Advil (two during the day, and one before bed) and it has done NOTHING to relieve the pain. I want to take another one but I cannot… I have been spitting in a cup all night because I can’t swallow my own spit, the pain is so severe. I’m not sure if I have a fever, but my forehead does feel warm to the touch. I keep overheating then getting chills. Also my stomach hurts, probably hunger since I was not able to eat much yesterday due to the throat pain. I can feel myself starting to get woozey from lack of sleep and possible dehydration. Again, I cannot swallow water at all, it is too painful.

At what point do I go to the ER? If I literally cannot swallow water without choking, gagging and crying in pain, won’t I become dehydrated? When should I quit with the home remedies and seek medical attention?