Well, it depends on the facts of your case. Ultimately, though, it is up to the DIstrict Attorney's office as to what charges will actually be filed against you. Often times, the police will arrest on a felony; however, the case ends up being charged as a misdemeanor. Talk to a criminal defense attorney in your area.
Much depends on the status of the building. For example, $80 shoes when the store is open is retail fraud. Taken from the hands of a person is robbery. But, if you enter a building when the store is closed and (for example) open a door, that is burlary. SEE a crimnal defense attorney at once. Do not make further confessions here on this public site. Maybe the police are just messing with you, but you may have a huge problem. See a lawyer.
We do not have a client/attorney relationship until you make an appointment, we discuss your case face to face, I accept a retainer, and we explictly agree to enter into representation.
You may, but not necessarily, could be charged with a second degree burglary by going into the business to commit a crime, but the DA would have to show intent to commit a felony prior to entering the business. Stealing an $80.00 pair of shoes is petty theft and a misdemeanor. Don't see this as any more than a misdemeanor.
The most important thing you can do now is remain silent and hire qualified legal counsel. Please remember . . . everything you say, do anybody, can be used by the prosecutor against you in court. Only communications you make with your lawyer are strictly confidential. Follow the advice of the other lawyers here and act quickly. Don't look for answers on the Internet, look for answers in the privacy of your lawyer's office. Good luck.
The police have no authority whatsoever to charge people with crimes. All they can do is arrest you and forward the information to the District Attorney. Only the District Attorney has the authority to charge people with crimes. The police can recommend a certain charge. But, the D.A. is under no obligation to accept it. Therefore, what the police told you is meaningless. It's possible the D.A. will reject the case, in which case you will be charged with NOTHING.
Stop worrying about what the police told you. Instead, contact a criminal defense attorney for advice on what, if anything, you should do at this point.