You can be charged for operating a motor vehicle without a license. This is if you actually have never had a license - if you have a license but it is suspended for some reason or another, depending on the reason you can be looking at a fine or jail time.
There are two ways that the Commonwealth can prove OUI. If your lawyer hasn't gone over this with you, you really need to speak to him or her. The Commonwealth can proceed under the theory that you were 'per se' intoxicated due to a BT of over .08 OR they can just try to prove that you were impaired while driving the motor vehicle without submitted any evidence.
Again, it sounds like you have a lawyer, you should only be discussing your case with him or her.
You need to have a conversation with your attorney regarding your concerns.
Also, you don't hire a lawyer to tell you what you want to hear, you hire a lawyer to represent you based on the information and facts at hand.
You didn't say if you have a record or give any other facts of the case, but technically you could get 2.5 years from and after (meaning consecutive not concurrent) on each of the larceny overs. It also depends on if you are being charged Federally or at the State level. You are more likely to be incarcerated at the Federal level.
I refer to Attorney Pang's answer. He explains all of the possibilities regarding your prior record. If you are worried I would hire an attorney to go with you to court. You don't want to risk having an entry on your adult record.
If you have concrete proof, you need to hire a lawyer.
Don't talk to the police or ANYONE about it except for an attorney.
Often when people try to honestly explain a situation, they get arrested.
If you can't afford a lawyer, you will have one appointed at your arraignment.