Fantastic Voyage_ Scene2 Render

This is my progression render of the scene 2 with spores movement, but still not the prefect lighting to me. The scene lighting changed after I put the spores with glow. I am going to revisit it till it looks nice.But also the scene looks different between render the image and render the whole scene.As it looks fine with the test image(fully render) but the final outcome looks dark and effects are a bit over. Does anyone know why?