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While I looked my friend´s face it came to my mind a small relief unknown.

'Relief' has more than one meaning and your sentence is accompanied by a photograph of a carved relief. So, I have a question, Mercedes: were you relieved, or were you thinking about the carved object?

A DEMOND IN THE HEAD

Be whith my friend to the doctor. She earts estranges sounds.
Well it´s very common when we are getting older, I told her, OK, OK,OK she told me, but I ear the sea´s waves in my head all the time and my body moves like a ship.
The doctor told her: the water in the ear´s laberint is very revolt, you can fall
While I looked my friend´s face it came to my mind a small relief unknown.

I would have said:

A DEMON IN HER HEAD

Be whith I went with my friend to see the doctor. She could earts hear estranges strange sounds. 
Well it´s very common when we are getting older, I told her, OK, OK,OK she told me, but I can hear the sea´s waves in my head all the time and my body moves like a ship. 
The doctor told her: "The water in the ear´s labyrinth is very revolt causing the problem, you can might fall." 
While I looked my friend´s face it came to my mind a small relief unknown I felt relieved, I don't know why.

A DEMON IN THE HEAD

I went with my friend to the doctor. She hears strange sounds in her ears. 

"Well, it's very commen when we are getting older," I told her. 

"Ok, Ok, Ok," she told me "but I hear the sea's waves in my head all the time and my body moves like a ship."

The doctor told her that the water in the ear's labyrinth is a problem and that she may fall down.

When I looked at my friend's face, I felt slightly relieved, but I don't know why.