How can it be that my render ridiculously slown down?

When I start my render it says it needs to render for 7 hours.

But after the 7 hours it's still rendering and it's almost frozen. It renders 1 frame per 10 seconds.

I have an Intel Core i5-5200U 2.20GHz CPU and I think it's a good one to render. I have seen almost every forum or video about it and I even tried Multiprocessing. But multiprocessing is not showing up. Please help!