Hi, I am having soar throat with small white patch on tonsil. I feel irritation which extendeds to back of ear. Can I take amoxilin 250?

Go see MD. There are only a few that can cause exudative pharyngitis as you described. Obviously one of them is strep. Resistance to penicillin now is high, the dose you have is low, and due to possible complications of this infection, it is best you are treated right, and right the first time.