Let’s say you wake up with a sore throat, a fever or an earache. Instead of urgent care, now you can go to Target. The retailer opened four in-store clinics in Southern California this week, in partnership with Kaiser Permanente. These kinds of mini-medical offices are a booming business right now. They reflect a shortage of primary care doctors and a changing insurance system. But some people say we should proceed with caution. We hear from one.