Updating a graphic

Question

I'm creating a game where you use arrow keys to move your character(it's a square right now) across the screen to doge incoming objects, and I am using a timer to update the object coming across the screen, but when I click my start button to make the object move across the screen, it just freezes everything and doesn't reupdate and redraw it like I want to, any idea how to fix it?

This is my code, sorry, it may be slightly to neat and kind of spacy so hope you don't mind scrolling a bit. I hope you guys can help, i'm in highschool in my programming 2 class and my teacher doesn't work much with timers, thanks for the help!

import java.awt.*;
import java.awt.event.*;
import javax.swing.Timer;

    public class Game2v4 extends Frame implements ActionListener, KeyListener
    {
        int x = 100;
        int y = 100;
        Timer myTimer = new Timer(10,this);


            Panel southPanel = new Panel();
                Button startButton = new Button("Start");
                Button clearButton = new Button("Clear");

        public Game2v4()
        {
            addKeyListener(this);
            setFocusable(true);
            this.setLayout(new BorderLayout());
                southPanel.setLayout(new GridLayout(1,2));
                    add(southPanel, BorderLayout.SOUTH);
                        southPanel.add(startButton);
                            startButton.addActionListener(this);
                        southPanel.add(clearButton);
                            clearButton.addActionListener(this);
addWindowListener
(
    new WindowAdapter()
    {
        public void windowClosing(WindowEvent e)
        {
            System.exit(0);
        }
    }
);
        }

        public void keyPressed(KeyEvent e)
        {
            if(e.getKeyCode() == KeyEvent.VK_UP)
            {
                y = y - 5;
                repaint();
            }

            if (e.getKeyCode() == KeyEvent.VK_DOWN)
            {
                y = y + 5;
                repaint();
            }

            if (e.getKeyCode() == KeyEvent.VK_RIGHT)
            {
                x = x + 5;
                repaint();
            }

            if (e.getKeyCode() == KeyEvent.VK_LEFT)
            {
                x = x - 5;
                repaint();
            }

                while(x >= 400)
                {
                    x = 1;
                    repaint();
                }

                while(x <= -10)
                {
                    x = 400;
                    repaint();
                }

                while(y >= 400)
                {
                    y = 1;
                    repaint();
                }

                while(y <= 0)
                {
                    y = 400;
                    repaint();
                }


        }

        public void keyReleased(KeyEvent e)
        {

        }

        public void keyTyped(KeyEvent e)
        {

        }

        public void actionPerformed(ActionEvent e)
        {
            Graphics g = getGraphics();
                if(e.getSource() == startButton)
                {
                    for(int i=250; i>0; i-=5)
                    {
                        g.drawRect(i,300,25,25);

                    }

                }
            this.requestFocus();
        }

        public void paint(Graphics g)
        {
            g.drawRect(x,y,25,25);
        }

        public static void main(String[] args)
        {
            Game2v4 f = new Game2v4();
                f.setBounds(50,100,400,400);
                f.setTitle("Gamev4");
                f.setVisible(true);
        }
    }