linked list Recursion not understanding result

For example lets run it like this How many nodes enter 2, so now my list is q.data= 2 which points to the next node which has a value 5, points to next value 6. At this point node Q. next equals null

DisplayList prints out 2 5 6.

That means Q is pointing to the head, How did that occur. And what makes Q.next change in DisplayList.

enter code hereimport java.util.*; // to import the class Scanner
import java.io.*;


public class BuildList{    
  public static void main(String[]  args ){

       node q = new node (0,null );
       q.buildmyList(q);  
       q.DisplayList(q);
  }
}
 class node
{
 int data;
 node next;
 public node()
 {data = 0; next = null;}
 public node(int x, node n)
{data = x; next =n;}




public void buildmyList(node q)
  {//node q = new node(0,null);
   node head = q;
  String oneLine;
  try{BufferedReader indata = new
      BufferedReader(new InputStreamReader(System.in));  
        System.out.println("How many nodes?\n"); 
   oneLine = indata.readLine();    
  head.data = Integer.parseInt(oneLine);
  for (int i=1; i<=head.data; i++)
  {System.out.println("A new value please\n");
    oneLine = indata.readLine();
    int num = Integer.parseInt(oneLine);
    node p = new node(num,null);
    q.next = p;
    q = p;
    //System.out.println("q = p qdata" + q.data  );
  }
}catch(Exception e)
{ System.out.println("Error --" + e.toString());}
}

public void DisplayList(node q)
{if (q != null)
{   System.out.println(q.data);
  DisplayList(q.next);

}
}

}