Twenty to thirty years ago these matters were far different than today. Penalties are now more severe, sickness the prohibited limits are drastically lower, doctor and lobbying groups have put Courts and Prosecutors under greater pressure to generate convictions. The days of being driven home by the kind-hearted officer after you acknowledged some poor judgment are long gone.
The tough reality is that there are active efforts to increase OVI DUI arrests and the questions that you are being asked are those taught to the Officer with the purpose of securing evidence for a conviction. This starts, sales in accordance with police training, before your car even comes to a stop.
There is no “set sentence” for first time OVI DUI offenders, only mandatory minimum sentences and penalties, more severe sentences and penalties can be and are imposed upon first offenders.