Criminal Law Questions? Ask a Criminal Lawyer.
You should get a lawyer. If you can't afford one, apply for the services of the public defender. That way, the lawyer can put on the defense and argue limited proof without you being put in the position of either incriminating yourself or lying. It doesn't sound like there is much proof in the case, but the second you go into court and start lying about being present in the store or not being present you are pretty much going to hang yourself and appear to have no credibility. If you have a lawyer, the lawyer makes all the arguments for you without putting you in that position.