Win32 message queue gets flooded when rendering with OpenGL

I encapsulated the the Windows API's CreateWindow around a class I call GLWindow, to which I render images using OpenGL. It took me some time, I even encapsulated the message queue, so basically my main function looks like that:

int main()
{
    GLWindow win;
    win.create("OpenGL Window", false, 1600, 800, -1, -1, true);
    win.hideCursor();
    win.moveMouseToCenter();

    init(); //initialize some opengl stuff

    bool quit = false;
    WindowEvent ev;

    while (!quit) {
        if (win.pollEvent(ev))
        {
            if (ev.type == ev.WindowClosed || (ev.type == ev.KeyboardKeyPressed && ev.keyboardKey.key == Keyboard::Key::Escape))
                quit = true;
            else
                handleEvent(ev);
        }

        updateCamera(&win);

        render(&win);
    }

    return 0;
}

The render function obviously takes the most time, and it causes the window procedure function to get flooded with messages, which eventually creates a delay in the WM_KEYDOWN and WM_MOUSEMOVE messages and because of that the camera update is delayed as well. (inside updateCamera())

Any idea what can I do?