You should observe silently that your cat is stressed or nervous for some reasons. These symptoms show that your cat is scared or there is something continuously bothering it. Is there any new pet arrived in your home recently? Try to feed your pets separately. Your cat requires your attention. Give it proper time to release its tension. Make sure that other family members also deal with it quite lovingly. Provide it with high quality food. I hope this behavioral problem of your cat will be resolved soon. If the problem persists take it to vet for a thorough check up because it can be a hairball as well.