Because this matter is so important you should really get a lawyer. Many factors such as age, prosecutor discretion, what judge you have, whether witnesses are credible all matter and that makes it near impossible to say what type of time you'll do if this is judged a crime.
You can miss defenses and say the wrong things if you are not represented by an advocate as your attorney.
You might find my Legal Guide helpful "How to Choose A Lawyer For You"
No one can know what the record is in the case because online we cannot find out any details. You need a lawyer. Check with a lawyer in your locale to discuss more of the details.
Good luck to you.
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Yes, you need a lawyer. A DUI is a very serious charge. Many bad things can happen if youn are convicted of it. You might go to jail, there will be fines, your license will be suspended, you car insurance costs will go up, you can have trouble with work or going to school, and many more problems. When you hire a lawyer be sure to hire a DUI specialist. Chech for one in your area at www.ncdd.com.