Is this shadow normal as per physics? The tube light above my curtain stick is producing two identical shadows on each side.
Whenever I switch off the tube light above the curtain stick both the shadows on the sides go away.
Are these shadows following physics? Can a single tube light produce two shadows on the two sides ?
I have attached one picture of the two shadows

 A: It is perfectly normal.

Can a single tube light produce two shadows on the two sides?

There are no two shadows. The two shadows that you are referring to are part of a bigger shadow. If your room was an infinite plane with no walls, you would see only one massive shadow of the curtain stick. But since you have two walls on each side, the extreme parts of this shadow get projected on the wall.
If you look carefully, the remaining part of the shadow will be visible on the tile. It may not be just as visible, as your tiles are highly reflective. But it is there, and you can verify that by holding a piece of paper and tracing out the shadow,
A: The 'curtain stick' is blocking the light from part of the tube light.
Other parts of the wall are illuminated by all the tube light.  The areas that appear  dimmer are illuminated by only part of the tube light.
A: To add to JohnHunter's answer:
If you draw straight lines ('ray tracing') from all points on the lightbulb to all points on the walls, you will see where rays are blocked by the curtain rod.  There are no direct lines which reach the shadowed areas.
