Why are the particles in my gravity simulation not working correctly even though i used the correct formula?

Question

i have been trying to make a particle gravity simulation thing using sdl2 and c++ but even though i used the correct formula its the same. the particles are getting attracted to the top right corner of the screen, it seems to fix itself if i increase the value of the gravitational constant but if i do so everything becomes really fast.

this is my code:

#include "SDL.h"
#undef main
#include <iostream>
#include <vector>
#include <cmath>
#include <random>
double Gravity = 1;
const int NumberOfParticles = 100;
bool isRunning = true;
int ParticleIndex = 0;
int MouseX = NULL;
int MouseY = NULL;
//References
int  DistanceY;
int x;
int y;
int ScreenHeight = 700;
int ScreenWidth = 700;
Uint32 TicksCounter;
double DeltaTime;

double  DistanceX;
//
double InverseDistance;
//
double Distance;
double Force;
double ForceY;
double ForceX;


struct Particle {
    double Mass[NumberOfParticles];
    double AX[NumberOfParticles];
    double AY[NumberOfParticles];
    SDL_Rect Particle[NumberOfParticles];
};
Particle Particles;
Particle OO;
int main() {
    //Setup
    SDL_Window* GameWindow = SDL_CreateWindow("Gravity Simulation.", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, ScreenWidth, ScreenWidth, SDL_WINDOW_SHOWN | SDL_WINDOW_RESIZABLE | SDL_RENDERER_PRESENTVSYNC);
    SDL_Renderer* Renderer = SDL_CreateRenderer(GameWindow, -1, 0);
    SDL_Event Event;
    SDL_Surface* WindowSurface = SDL_GetWindowSurface(GameWindow);
    //GameLoop
    while (isRunning) {
        srand(time(0));
        //Calculate DeltaTime
        DeltaTime = (SDL_GetTicks() - TicksCounter) / 1000.0;
        TicksCounter = SDL_GetTicks();
        std::cout << "DeltaTime : " << DeltaTime << std::endl;
        SDL_GetMouseState(&MouseX, &MouseY);
        while (SDL_PollEvent(&Event)) {
            if (Event.type == SDL_QUIT) {
                isRunning = false;
            }
            if (Event.type == SDL_KEYDOWN) {
                //Keyboard Inputs
            }
            if (Event.type == SDL_MOUSEBUTTONDOWN) {
                //Mouse Inputs
                if (Event.button.button == SDL_BUTTON_LEFT) {
                    //Add Particle
                    Particles.Particle[ParticleIndex].x = MouseX;
                    Particles.Particle[ParticleIndex].y = MouseY;
                    Particles.Particle[ParticleIndex].w = 5;
                    Particles.Particle[ParticleIndex].h = 5;
                    Particles.Mass[ParticleIndex] = 10 + rand() & 10;
                    ParticleIndex++;

                }
                if (Event.button.button == SDL_BUTTON_RIGHT) {
                    //Add Particle
                    Particles.Particle[ParticleIndex].x = MouseX;
                    Particles.Particle[ParticleIndex].y = MouseY;
                    Particles.Particle[ParticleIndex].w = 25;
                    Particles.Particle[ParticleIndex].h = 25;
                    Particles.Mass[ParticleIndex] = 1000;
                    ParticleIndex++;
                }

            }
        }
    
        for (y = 0; y < ParticleIndex; y++) {
            for (x = 0; x < ParticleIndex; x++) {
                if (x != y) {
                    DistanceX = Particles.Particle[x].x - Particles.Particle[y].x;
                    DistanceY = Particles.Particle[x].y - Particles.Particle[y].y;
                    Distance = std::sqrt(DistanceX * DistanceX + DistanceY * DistanceY + 1);
                    InverseDistance = 1.0 / Distance;
                        //Calculat Forces
                    std::cout << "Particle Index :" << ParticleIndex << std::endl;
                    //Calculate Gravity 
                        std::cout << "Mass :" << Particles.Mass[x] << std::endl << "Distance :" << Distance << std::endl;
                        Force = ((Gravity * (Particles.Mass[x] * Particles.Mass[y])) / (Distance * Distance)) ;
                        Particles.AX[y] += (Force * DistanceX / Particles.Mass[x]) * DeltaTime;
                        Particles.AY[y] += (Force * DistanceY / Particles.Mass[x]) * DeltaTime ;
                }
            }
        }
        for (y = 0; y < ParticleIndex; y++) {
            Particles.Particle[y].x += Particles.AX[y];
            Particles.Particle[y].y += Particles.AY[y];
        }
        //Rendering
        SDL_SetRenderDrawColor(Renderer, 255, 255, 255, 255);
        SDL_RenderClear(Renderer);
        SDL_SetRenderDrawColor(Renderer, 0, 0, 0, 255);
        for (y = 0; y < ParticleIndex; ++y) {
            SDL_RenderFillRect(Renderer, &Particles.Particle[y]);
        }
        SDL_RenderPresent(Renderer);
    }
}

i have tried using other formulae, thought that maybe the initial positions of the other particles is at 0,0 (the top right corner), to check if the other ones were going there because of that i made the number of particles just 2, but they too were getting attracted to the corner.