What Is The Treatment For Red Itchy Dots All Over The Body?

i was under a tree and a caterpillar type creature landed on me. it started to itch. i scratched. it started with a few red itchy dots. now it's spread all over and seems to be spreading even more. i was given mometasone furdate by the pharmacist. is this the right medicine? and is there anything else i can do to reduce the spread and itching?