Priority queue implementation

I was trying to build a priority queue but there seems to be some inconsistency when I tested it. I overrode method compareTo() but somehow it return student with the youngest age. Why is that ? Shouldn't it be the student with age 22 (highest) ? Here is the code:

public class Student implements Comparable<Student> {

   private String name;
   private int age;

   public Student(int i) {
      age = i;
   }
   public int getAge(){
    return this.age;
   }

   public int print(){
    return age; 
   }
   @Override
   public int compareTo(Student s) {
    if(this.age < s.getAge()){return -1;}
    else if(this.age > s.getAge()){return 1;}
    else{return 0;}
   }
    public static void main(String[] args) {
        Queue<Student> q = new PriorityQueue<Student>();
        q.offer(new Student(21));
        q.offer(new Student(18));
        q.offer(new Student(22));

        Student s = q.poll();
        System.out.println(s.print());
}