Hi, I Was Wondering. Is The Mastoid Bone Palpable? I

Hi, I was wondering. Is the mastoid bone palpable? I have two bony humps behind my ears on both sides, slightly more prominent on the right side and I am growing concerned and I am not sure if they have always been there or not after some research I am inclined to believe that it is my mastoid bone. I phoned a friend and asked him if he felt the same things behind his ears and he said he does. I wanted to consult someone online before I go see a doctor in person. Thank you.