Is there something wrong with my pussy?

My cat (or kitten rather) is four months old and recently she has been randomly going into her litter box and dig all of her liter to one side of the box to the point where litter( A LOT of litter) is falling out of it. sometimes when she does this she doesn't even use the bathroom. she will do this regardless of how clean or dirty it is. shes been doing it for a while and i thought it was because her box was too messy so i tried cleaning it completely last week (emptied the box, scrubbed it, and put all new litter) but just yesterday she did it worst than she ever has before. i have to sweep every day and its annoying any suggestions? I always use the same litter and she only does this when she is alone if some one is in the room she wont do it, however if you walk in on her doing it she wont stop.