Its ok there are some big things that need to be worked on. Mainly blending your render into the background. It looks like you did some outer glow or something on the render and didnt really match the c4d with the render. The flow is pretty good though. It draws your attention to your focal. Lighting is in a big need here, you need to find a light source on the render and make light in ur bg. Ur light looks scatered and doesnt work. The dodge and burn tool is amazing for adding great depth and blending. Also gradient maps and levels and curves and photo filters will also help with depth and blending. Keep it up though