My 8 yo male cat vomited Monday, yesterday and today. Only once each day. Should I be alarmed? He doesn't have a history of hair balls but I guess there's a first time for everything? I figured I'd give it a few more days and if he vomits again we'll be off to the vet. I just wanted to get some feedback as to what could be the cause. Im not overly alarmed as it was only once each day.