Python, Pygame, my while loop breaks before it ends and i dont kno how to fix it

Question

Im working on a school project on a motion projectile but my while loop breaks before it ends.

import pygame, sys
from pygame.locals import *
from math import *

def rot_center(image, center_angle):
    orig_rect = image.get_rect()
    rot_image = pygame.transform.rotate(image, center_angle)
    rot_rect = orig_rect.copy()
    rot_rect.center = rot_image.get_rect().center
    rot_image = rot_image.subsurface(rot_rect).copy()
    return rot_image

pygame.init()

FPS = 144 
fpsClock = pygame.time.Clock()

SCENE = pygame.display.set_mode((1280, 720), 0, 32)
pygame.display.set_caption('Domača naloga')

backgroundImg = pygame.image.load('images/background.png')
cannonBaseImg = pygame.image.load('images/base.png')
cannonImg = pygame.image.load('images/cannon.png')
ballImg = pygame.image.load('images/cannonBall.png')
enemy = pygame.image.load('images/enemy.png')

cannonBasePos = (9,490)
cannonPos = (-5, 480)
ballPos = (22,510)
enemyPos = (40, 400)

cannonImg = pygame.transform.rotate(cannonImg, -15)

ang = 45
cannonMovImg = rot_center(cannonImg, ang)

# bug: backgoround image dissapears and it bugges green
SCENE.blit(backgroundImg, (0,0))
SCENE.blit(cannonMovImg, cannonPos  )
SCENE.blit(ballImg, ballPos)
SCENE.blit(cannonBaseImg, cannonBasePos)
SCENE.blit(enemy, enemyPos)

t = 0 
s = ballPos 
v = (0, 0) 
vm = 100 
launched = False 

while True: #<-- while starts here
    dt = fpsClock.tick(FPS) 
    if launched:
        t = t + dt/250.0 # cajt is clocka
        a = (0.0, 10.0) # acceleration
        v =  (v0[0] + a[0]*t, v0[1] + a[1]*t) # spazz out nad 1000 !!!
        vm = sqrt(v[0]*v[0] + v[1]*v[1])
        s0 = ballPos # poz
        s = (s0[0] + v0[0]*t + a[0]*t*t/2, s0[1] + v0[1]*t + a[1]*t*t/2)
        if s[1] >= 510: # tla
            launched = False

    font = pygame.font.Font(None, 30)

    text_ang = font.render("Kot = %d" % ang, 1, (10, 10, 10))
    text_ang_pos = (1050, 50)

    text_vm = font.render("Hitrost = %.1f m/s" % vm, 1, (10, 10, 10))
    text_vm_pos = (1050, 80)

    text_stat = font.render("Statistika:", 1, (10, 10, 10))
    text_stat_pos = (1050, 20)

    text_x = font.render("Dolžina = %.1f m" % s[0], 1, (10, 10, 10))
    text_x_pos = (1050, 110)

    text_t = font.render("Čas = %.1f s" % t, 1, (10, 10, 10))
    text_t_pos = (1050, 140)


    SCENE.blit(backgroundImg, (0,0))
    SCENE.blit(cannonMovImg, cannonPos)
    SCENE.blit(ballImg, s)
    SCENE.blit(cannonBaseImg, cannonBasePos)
    SCENE.blit(enemy, enemyPos) #<--- while loop breaks here
    SCENE.blit(text_t, text_t_pos)
    SCENE.blit(text_stat, text_stat_pos)
    SCENE.blit(text_vm, text_vm_pos)
    SCENE.blit(text_x, text_x_pos)
    SCENE.blit(text_ang, text_ang_pos)


    for event in pygame.event.get():
        if event.type == QUIT:
            pygame.quit()
            sys.exit()
        elif event.type == KEYDOWN:
            if event.key == K_SPACE:
                ballPos = (0,478)
                s = ballPos
                t = 0
                launched = True

                v0 = (vm*cos(radians(ang)), -vm*sin(radians(ang)))

    keystate = pygame.key.get_pressed()

    if keystate[K_LEFT]: 
        ang+=2
        if ang > 90:
            ang = 90
        cannonMovImg = rot_center(cannonImg, ang)

    if keystate[K_RIGHT]: 
        ang-=2
        if ang < 0:
            ang = 0
        cannonMovImg = rot_center(cannonImg, ang)

    if keystate[K_UP]: 
        vm+=2

    if keystate[K_DOWN]: 
        vm-=2

    pygame.display.flip() #<-- while should end here 

I've tried everything but even my teacher doesnt know the anwser. He said it's a bug in Python 3.6.3. Any ideas. I've researched for the past week and im frustrated. If anyone has any ideas please let me know. Thanks for your anwsers in advance