Why is paintComponent drawing JMenu in addition to red circle?

Question

The paintComponent method not only draws the red circle but also a copy of the JMenu despite the fact that that area being drawn on is a JPanel not a JFrame

Screenshot of the issue

I tried doing super.paintComponent(g) but i want it to leave a trail as I am working on a paint app for Java.

Here is the primary code:

Main.java

public class Main {

    public static void main(String[] args) {
        new MainApplication();
    }

}

MainApplication.java

import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.Toolkit;

import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;

//import menu_items.PicImport;

public class MainApplication extends JFrame {
    /**
     * 
     */
    private static final long serialVersionUID = 1L;
    private Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();
    private double width = screenSize.getWidth(), height = screenSize.getHeight();
    //ButtonsMenu bm = new ButtonsMenu();
    //TopMenu tm = new TopMenu();
    CanvasPanel cp = new CanvasPanel();
    JMenu fileMenu,helpMenu;
    //PicImport pi;
    JMenuBar jmb = new JMenuBar();
    MainApplication() {
        this.setSize(new Dimension((int) width - 20, (int) height - 60));
        this.setTitle("Canvas Painter");
        this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        this.setVisible(true);
        this.setResizable(false);
        this.setLocationRelativeTo(null);
        jmb.add(new JMenuItem("asd"));
        this.add(cp,BorderLayout.CENTER);
        //this.add(bm, BorderLayout.WEST);
        this.setJMenuBar(jmb);
        //bm.setLayout(new FlowLayout(FlowLayout.LEFT));
        //this.setLayout(null);
        this.setVisible(true);

    }
}

CanvasPanel.java

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

/**
 * This class represents the primary panel in which the user will be drawing on
 * 
 * @author 
 *
 */
public class CanvasPanel extends JPanel implements MouseListener, MouseMotionListener {
    int mouseX, mouseY;
    /**
     * 
     */
    private static final long serialVersionUID = 1L;

    /**
     * Default Constructor for the CanvasPanel Class
     */
    public CanvasPanel() {
        addMouseMotionListener(this);
        setVisible(true);
    }

    @Override
    public void mouseClicked(MouseEvent e) {
//      mouseX = e.getX();
//      mouseY = e.getY();
//      repaint();
    }

    @Override
    public void mousePressed(MouseEvent e) {
        mouseX = e.getX();
        mouseY = e.getY();
        repaint();
    }

    @Override
    public void mouseReleased(MouseEvent e) {
        // TODO Auto-generated method stub

    }

    @Override
    public void mouseEntered(MouseEvent e) {
        // TODO Auto-generated method stub

    }

    @Override
    public void mouseExited(MouseEvent e) {
        // TODO Auto-generated method stub

    }

    @Override
    public void mouseDragged(MouseEvent e) {
        mouseX = e.getX();
        mouseY = e.getY();
        System.out.println("Lmao");
        repaint();

    }

    @Override
    public void mouseMoved(MouseEvent e) {
        // TODO Auto-generated method stub

    }

    @Override
    public void paintComponent(Graphics g) {
        Graphics2D g2D = (Graphics2D) g;
        g2D.setColor(Color.RED);
        g2D.fillOval(mouseX - 15, mouseY - 20, 30, 30);

    }
}