this morning i noticed 3-4 ich spots. after 12 hours they were dissapeared!!!
Could this be ich?...

I don't know can you give us more info???

Haven't you been treating for something recently?

if it is ich and you havent been treating it then you need to do something quickly as they will burst from the cyst and your fish will have more.
the best treatment for it is dosing the tank with aquarium salt and adding it 1 level teaspoon per gallon every 12 hours until you get to .3%

I have been medicating the tank for ich.
The old "ich" (dont know if it was ich) was gone.
I medicated the tank twice in 7 days. After this I did 3 or 4 15-20% water changes.
Shall I use carbon before adding salt?

i think the water changes would have got rid of any treatment still left, but add the carbon anyway as im sure you can treat with salt with carbon in it. keep an eye on them k and if you see any more spots then go with the salt.