Help in PIC programming during "mydata==a" is running

   do{

      if(kbhit())
      {mydata=getch();
         mystat=1;}

      if(mystat==1)
      {

      if(mydata=='a' || mydata=='A') // Junction 1
      {
      //green at junction 1
      output_high(PIN_D5);
      output_low(PIN_D6);
      output_low(PIN_D7);
      
      output_low(PIN_E2); //<--- how to terminate this during execution of mydata=='a'
      }

      mystat=0;
   }

     else if (mystat==0)
     {
     //junction 1
     if(input(PIN_E2)==0)
      {
      //green
      output_high(PIN_D5);
      output_low(PIN_D6);
      output_low(PIN_D7);
      junction2();
      delay_ms(2000);
      //yellow
      output_high(PIN_D6);
      output_low(PIN_D7);
      output_low(PIN_D5);
      delay_ms(2000);
      //red
      output_high(PIN_D7);
      output_low(PIN_D6);
      }
}
while(1);