My PYQT shape instances are confined to a corner on the screen

Question

I've been developing an application that takes coordinates from a serial port and creates a shape at said coordinates. The coords given from the serial port are in centimeters, so I convert them to pixels. (This conversion has been tested and works). However, my shapes seem to be confined to a box in the upper left-hand corner of my screen. Here you can see the result of multiple coordiantes tested. Shape Image. The circles are being cut off.

I've included my code below. Apologies if this is a newbie question, it's my first time using PYQT.

import sys
from PyQt6.QtWidgets import QApplication, QMainWindow, QWidget, QLabel, QVBoxLayout
from PyQt6.QtCore import Qt, pyqtSignal, QObject, QThread
from PyQt6.QtGui import QPainter, QPen, QBrush, QColor, QPixmap
import time
from backend.IRserial import IRserial






class CircleWidget(QWidget):

    def __init__(self, xCoord=0, yCoord=0):
        super().__init__()
        self.xCoord = xCoord
        self.yCoord = yCoord



    def paintEvent(self, Event):

        painter = QPainter(self)
        painter.setRenderHint(QPainter.RenderHint.Antialiasing) 
        
        # Set the pen (outline) and brush (fill) for the circle
        pen = QPen()
        pen.setColor(QColor("blue"))
        pen.setWidth(2)
        
        brush = QBrush()
        brush.setColor(QColor("lightblue"))
        brush.setStyle(Qt.BrushStyle.SolidPattern)
        
        painter.setPen(pen)
        painter.setBrush(brush)
        
        # Draw a circle at position (100, 100) with a radius of 50
        painter.drawEllipse(self.xCoord, self.yCoord, 50, 50)




class find_coords(QThread):
    event_ready = pyqtSignal(int, int)
    

    # This method runs in a separate thread
    def run(self):

        xMax = 27 #update this when you figure  out the actual dimensions
        yMax = 16.5

        app = QApplication.instance()

        # If the application is running
        if (app is not None):

               #--- DPI ---
            screen = app.primaryScreen()
            dpi = screen.logicalDotsPerInch()
            # ------

            sr = IRserial()
            while 1:
        
                l = sr.get_packet()
                x = l[0]
                y = l[1]


                # ------ Convert x/y to top down coords ------
                if (x < 0):
                    x = xMax - abs(x)
                else:
                    x = xMax + x
                
                if (y < 0):
                    y = yMax + x
                else:
                    
                    y = yMax - abs(y)
                #------------------------------------------
                
               
                # ---- Pixel representations of x and y ------
                xPix = (x * dpi) / 2.54 # 1 inch = 2.54 cm
                yPix = (y * dpi) / 2.54
                #------------------------------------------


                print(f"xPix: {xPix}")
                print(f"yPix: {yPix}")

                self.event_ready.emit(xPix, yPix)
                
        
    

def print_coords(x, y, window):

    circle_widget = CircleWidget(x, y)
    lay = window.layout()
    lay.addWidget(circle_widget)

    




def main():

    app = QApplication(sys.argv)
    # ---------   Create and scale window ---------
    window = QMainWindow()
    window.setWindowTitle("Scaled Window")
    window.showMaximized()  # Show the window maximized
    # Get the screen size
    screen = app.primaryScreen()
    size = screen.availableGeometry()
    # Set the window size to match the screen size
    window.setGeometry(size)
    #Removes window frame and title bar
    window.setWindowFlags(Qt.WindowType.FramelessWindowHint)
    #--------------------------------------------
            

 

    image_widget = QWidget()
        
    # Create a QVBoxLayout to center the image vertically
    lay = QVBoxLayout(image_widget)
    lay.setAlignment(Qt.AlignmentFlag.AlignCenter)

        
    label = QLabel()
            
    # Load an image from a file and set it to the label
    pixmap = QPixmap("bullseye.jpg")


    label.setPixmap(pixmap)
            
            
    lay.addWidget(label)
    window.setCentralWidget(image_widget)




    #--------- Threading
    find_coords_thread = find_coords()
    find_coords_thread.start()
    #-------------------



    slot_function = lambda x, y: print_coords(x, y, window)
    find_coords_thread.event_ready.connect(slot_function)


    window.show()
    sys.exit(app.exec())
    

if __name__ == '__main__':

    main()

I've tried changing the layout type and creating the layout in the print_coords function.