Respectfully, the FBI does not charge you with trademark infringement. While the FBI may investigate a trademark infringement, the Department of Justice or the local United States Attorney's Office would bring charges of trademark infringement.
Further, your question is posted in the criminal defense forum, but you need a patent/trademark attorney. This is why no one has answered your question thus far.
Sounds like a possible counterfeiting rap - you need to hire a criminal defense attorney locally to accompany you to the FBI interview. But I suspect you know that by now.
