Flashing traffic and pedestrian light with buzzer

int carRed = 12;
int carYellow = 11;
int carGreen = 10;
int pedRed = 9;
int pedGreen = 8;
int buzzer = 13;
int button = 2;
int crossTime = 5000;
unsigned long changeTime; // since button pressed

void setup(){
   pinMode(carRed,OUTPUT);
   pinMode(carYellow,OUTPUT);
   pinMode(carGreen,OUTPUT);
  pinMode(pedRed,OUTPUT);
  pinMode(pedGreen,OUTPUT);
  pinMode(buzzer,OUTPUT);
 pinMode(button,INPUT);

  // turn on the default mode
 digitalWrite(carGreen,HIGH) ;
 digitalWrite(pedRed,HIGH);
}

void loop(){
  int state = digitalRead(button);
  // check if button has been pressed and its over 5 seconds since last press
  if (state == HIGH && (millis() - changeTime)>5000){
    changeLights();
  }
}

void changeLights(){
    digitalWrite(carGreen,LOW);
    digitalWrite(carYellow,HIGH);
    delay(2000);

    digitalWrite(carYellow,LOW);
    digitalWrite(carRed,HIGH);
   delay(1000);

   digitalWrite(pedRed,LOW);
   digitalWrite(pedGreen,HIGH);

    beep(crossTime,250,250,false);
    beep(4000,100,100,true);


    // turn red back on for pedestrians
   digitalWrite(pedRed,HIGH);
  delay(1000);

   digitalWrite(carYellow,HIGH);
   digitalWrite(carRed,LOW);
   delay(1000);

   digitalWrite(carGreen,HIGH);
   digitalWrite(carYellow,LOW);

 changeTime= millis();
}

// beep for total of how long, time on, time off, and whether to flash
// the light at the same time
void beep(unsigned int time,int intervala,int intervalb,boolean flash){
   unsigned long beepTime = millis();
   unsigned long stillBeeping = millis();
   while((stillBeeping - beepTime)<time){
     digitalWrite(buzzer,HIGH);

     if(flash == true){
       digitalWrite(pedGreen,HIGH);
     }
     delay(intervala);

     digitalWrite(buzzer,LOW);
     if(flash == true){
       digitalWrite(pedGreen,LOW);
     }

     delay(intervalb);
     stillBeeping = millis();

   }
}