First of all : welcome to the world of Pettalkers !!! It's so much fun to be here !!!!
How long do you have that cat of yours ??? If she is new , then do not worry ; she (or he) has to get used to its new home and family !!!!
But as Karen says , the cause can also be a medical one ; I would try to see a vet as soon as possible !!
Please get us updated on how it goes !! Success to you !!!