Got a sore throat very suddenly, lasted for a week. i have red lumps on the back of my throat and my tonsils are swollen. what could it be?

Pharyngitis: That's a fancy medical term for a throat infection. Any number of bacteria or viruses could cause this. I'm sure you've heard of 'Strep throat' for example. The best thing to do, is see a doctor who can take a culture or perform other tests to make the best determination of what you have. Then, the treatment can be targeted. Sometimes 'no answer' is found, and you just have to deal with symptoms