After mouse click image disappears and shows up in new random position. How can I check the new position? (processing)

I need help with my code in processing. It is actually a short and easy code, but I am a beginner in programming, so for me seems everything difficult... :(

My goal is... - to click on an image. - After the mouse click, the image should disappear - and show up in a new random position. - Then I should be able to click on the image in the new random position, - and it should do the same again: disappear and show up in a new random position. - and so on.

I have written some code (see below), but it does not work properly. I would really appreciate it if someone could help me to find out, what is wrong with my code. Thank you very much in advance! :)

Here is my code:

PImage pic; 

// Declare variables for the picture
float pic_x; 
float pic_y;
float pic_r = 100;

float pic_x_new = random(0, 400);
float pic_y_new = random(0, 400);

boolean mouseOverPic;

void setup(){
 size(500,500);
 background(0,100,0);

//loading the picture
pic = loadImage("pic.png");
image(pic, pic_x, pic_y, pic_r, pic_r); 
}


void draw(){

 mouseOverPic = mouseX <= pic.width 
 && mouseX >= pic_x 
 && mouseY <= pic.height 
 && mouseY >= pic_y;

if (mousePressed && mouseOverPic) {
  background(100);
  image(pic, pic_x_new, pic_y_new, pic_r, pic_r);  
 }  
}