**Problem Solved, for some reasson i have pressed CRTL+R which means no realtime render in the editor. You can find this ‘‘realtime render’’ option in the image above on the left corner on the Arrow pointing down. However, the shadows thing are strange, it seemed my invisible walls/meshes i use for collision had been triggered to cast shadows again. You can unclick cast shadows by clicking on your Mesh and under the Details tab>Lightning>Cast shadows. **
Out of nothing the smoke particle systems are not working anymore, and my invisible collision walls show strange shadows on the ground, sometimes making curves where the walls are only straight geometry blocks in first place.
I have included an image where you can see the particle system is not working in the editor plus the strange shadows. When rebuilding the problem is not solving. It seems something has been broken?
