If you paid it back before leaving the store it is unclear if a crime is committed. If you paid it back later there may or may not be criminal charges filed. Some stores won't report to the police unless you don't pay them. You will only be charged if the police become involved. You should politely decline to make a statement to the police if charged and then seek an attorney to help you. If no one has contacted that might mean the store accepted payment and won't contact the police.
These statements do not constitute legal advice. They are meant to be general in nature, for any specific legal questions you should always seek the counsel of an experienced attorney.
I'm also here in Albuquerque, I might be able to help you answer this question. If you say you "stole" merchandise, I'm guessing that they are saying you tried to leave the store with it or were concealing it. With that being said, you can still be charged for a crime, since it was actually completed. It does not matter that the $48 was actually paid back or not.
The big factor would then be if the store was motivated to report it to the police. If so, then you still may have a case. Now, you would not have to worry about restitution (that is when the court orders you to pay back anything owed to the other party), but you do have to keep your record clean.
If you don't have a history and are a student, there is a good possibility that you can work something out to where this would not go down as a conviction on your record. Most Albuquerque officers can be understanding and easy to work with. This does not mean that you will not have some punishment; I would expect maybe a class on decision making or some community service would likely be a result - but you do have a fair chance at keeping this off of your record. This is a charge you definitely DO NOT want on your record because theft is considered a "crime of moral turpitude", which means this can affect your future employment when you graduate school.
If you have any follow up questions, let me know. All the best!