Matt Ryan had around that many his last college season too.
Stats don't tell the whole story. Some of the ints are Winston's fault and some are on the fault of the receivers but trying to translate college stats into the pros is just silly. If you watched him over last season, the ints come from him staring down his receiver and not looking off the defenders while others are WRs giving up on a play. His mistakes are correctable. I wouldn't be surprised if he throws 18 or more ints this year but he will be a future stud.