Off-By-One Error in Java Queue Implementation

I'm a beginning programmer working on a from-scratch queue implementation, and for some reason I've got an off-by-one error. Here's my class:

class Queue
{
   // pointer to first node in stack
   public Node oldest;
   public Node youngest;
   public int queueSize = 0;

   // constructor
   public Queue(){
       oldest = null;
       youngest = null;
       queueSize = 0;
}

   public boolean isEmpty() {
       return oldest == null;
   }

   public boolean add(Node newNode){ 

   if(isEmpty()){
       oldest = newNode;
   }else{
       newNode.next = youngest;
       oldest.next = youngest;
       youngest = newNode;
       }

       return true;
   }


   public Node remove(){
       Node temp;
       temp = oldest;
       if( oldest != null){
           oldest = oldest.next;
           temp.next = null;
       }
       queueSize--;
       return temp;
   }

   public void showQueue(){
       Node p;    
       for(p = oldest; p != null; p = p.next){
         p.toString();
       }
   }
}

If I fill the Queue using a loop, and then do showQueue(), I'm always one less than I should be. For example, this, from my main:

      // build the queue
      for (int k = 0; k < 5; k++)
      {
         node1 = new Node();
         queue2.add(node1);
      }

      //show the stack
      queue2.showQueue();

gives the result

(Node) (Node) (Node) (Node)

or only four nodes. What's going on here?

Thanks in advance.