How can I treat this sore throat and how long will it last?

I've had a sore throat that started thursday night. On Friday I woke up with pain and it got better then got bad at night. Today being saturday it has hurt most of the day. I've tried gargling warm salt water, cepacol, tylenol, ibuprofen, ive been drinking water, had yogurt, jolly ranchers, and i have gotten tons of rest and i still feel horrible. I also feel weak , and lightheaded.. how can i treat this and how long does it last?