IS THIS NORMAL????

MMPh
So my baby is 3 months going to 4 months Nov 3rd.
I just recently noticed that he keeps on putting his hand behind his right ear towards the back of his head. 
He doesn't have high temperature. I don't feel any bump and nothing unusual in the area he is touching. 
I'm worried because he's never done this. Is this normal??? Could it be sign of teething??