Strep throat!!!!! A kid had it and is contagious! plz read!?

So i was in my 6th grade science cl ( i AM 13..) when a kid who had had STREP THROAT had been gone for more than a week. He was coughing,and his voice was weak and she kept coughing and spitting on me. I kept saying, "STOP!!!!!" and all he said was "Hehe!" Ughhhh these people bother me! Now I am afraid i will get it. I dont know if he took meds. :( I have done the salt water mouth-wash thing. So I was wondering, are there any things I can do to help myself!? PLEASE! I will choose a best answer ! :) Please! THANK YOU SO MUCH! ILY! :)