hard knot under just under head

I have recently gotten a small hard knot that is painless just below my head on the right side. It is colorless unless i press on it and it just turns white like the rest of the skin but I can see the not it is the size of a small pebble or so. Any ideas???

Is it located in a vein? There are a lot of veins around there and if its hard like a pebble rather than pliable it could be a thrombosis, the position is somewhere I don’t remember seeing posted before but I’m not sure what else it would be, unless its more like a blister or you can relocate it some way by pushing it around.

I cant really tell if its in a vein or not it looks like a little pebble under the skin. cant really moved it around much no pain at all either. Should I stop PE all together?