First, the grocery store security has the ability to detain you for a reasonable time and using reasonable force to determine if you had any merchandise on you. You may have a challenge to the discovery of the drugs if the grocery store security can articulate what he thought/saw you take from the store and whether what you allegedly took could have fit in your small pocket. If you were accused of taking a dozen eggs, you may have an argument against him searching your small pocket.
Keep in mind that every state has different laws and procedures so NJ may operate differently than my experience in Illinois. You should speak with an attorney regarding this matter.Ask a similar question