Very sudden sore, swollen throat, red dots on roof of mouth. completely fine when i woke up this am. what could it be?

Petechiae: Everyone wants to learn a new word right? Were the spots there last night and went away or did the sores come up this afternoon? Either case warrants a peek from a dentist. You may have a sudden onset virus, allergic reaction to a food or petechiae (sometimes painful red dots on the roof of your mouth from trauma). As always if you can't breathe or swallow 911. I hope they feel better soon!

See a doctor: You may have a viral infection. Please see your doctor.

Virus: Could be a secondary hermetic outbreak. Most people had the chicken pox as a child and have the herpes virus lying dormant in their system. A herpes outbreak in the mouth can look like little spots with a red ring around them. Give it a week to ten days and it may be gone.