Project problem (Bullet hell)

Projects General Guidance
1 
#include <LiquidCrystal.h>

LiquidCrystal lcd(12, 11, 5, 4, 3, 2);
int i;
int j;
int clockoboi = 0; //countdown till the next movement of bullets
byte customChar[] = { //stickperson
  B00110,
  B00110,
  B01110,
  B10101,
  B10101,
  B01010,
  B01010,
  B01010
};
int up = 9; //buttons
int down = 8;
bool pos = 0; //location of the stickman
char bullets[2][15]; //the state of each bullet, '-'-exists, ' '-doesn't

void setup() {
  lcd.begin(16, 2);
  lcd.createChar(0, customChar);
  pinMode(up, INPUT); 
  pinMode(down, INPUT);
  
  for(i = 0; i < 2; i++){ //set up bullets
    for(j = 0; j < 15; j++){  
      bullets[i][j] = ' ';
    }
  }
  randomSeed(analogRead(0));
}

void loop() {
  if(digitalRead(up)){
    pos=0;
  }else if(digitalRead(down)){
    pos=1;
  }else{
    pos=pos;
  }
  lcd.setCursor(0,pos); //stickfig movement
  lcd.write(byte(0));
  delay(200);
  lcd.clear();
  if(clockoboi==10){ //time to move bullets?
    
  clockoboi=0;
  if(bullets[0][pos]=='-'){ //cheks if bullets hit the stickfig
    lcd.print("You lost");
    delay(1000);
    exit(0);
  } 
  for(j = 0; j < 2; j++){ //bullets move forward
    for(i = 0; i < 14; i++){  
      bullets[j][i] = bullets[j][i+1];
    }
    if(random(5)==1){ //a new bullet appears
      bullets[j][15]='-';
    }else{
      bullets[j][15]=' ';
    }
  }
  
  for(j = 0; j < 2; j++) //bullet display
  {
    lcd.setCursor(1,j);
    for(i = 0; i < 16; i++)
    {  
      lcd.print(bullets[j][i]);
    }
  
  
  }
  }
    clockoboi++; 
}

I have a problem with this project, please help.
This is supposed to be a game on an lcd, operated with two buttons, you move up and down and you should avoid a rain of bullets. Although the moving works, bullets don't generate properly, in fact they don't generate at all, does somebody know how can I fix this problem and what might be causing it?

2 
for(i = 0; i < 16; i++)
    {  
      lcd.print(bullets[j][i]);
    }

What is the maximum permissible value of i?

3

AWOL:

for(i = 0; i < 16; i++)

{ 
      lcd.print(bullets[j][i]);
    }


What is the maximum permissible value of i?

15

4

Have another go.

5 
for(i = 0; i < 15; i++)
    {  
      lcd.print(bullets[j][i]);
    }

I've corrected it to this, but it still doesn't work

6

Your bullet generation code contains the same mistake.

7 
bullets[j][15]='-';