Is it normal to be always spelling certain words in your head ?

SO, ever since a few years ago, whenever I hear a word, like any word its not even any particular word, just a random word, I spell it out in my head. But its weird, I imagine to collums in my head, Ill spell the word out correctly(ex:vulnerable), with each letter going back and forth each side as i spell. Then ill do the same and spell it the shortest way possible(ex:vnrbl), then Ill spell it how it sounds(ex: vulnrubul) Then ill spell it the longest way possible with the most silent letters ever(ex:hvhuhlnherauhblhe). And if the last word ends on the left side, of the column, ill get so irritated. But if it ends on the right side, Ill be happy and be able to move my thoughts onto whatever. I used to just think this stuff in my mind, but now i have been starting to spell it out with my fingers. Which is really really annoying. But this little obsessive habit, has just been so distracting, like I cant not do it. Is that normal ?