It sounds like you have two questions: 1) can your ex convince a judge to completely change the status quo regarding you and your son; and 2) can your ex make your life miserable by harassing you in the guise of a lawsuit. Based on what you wrote, the answer to the first question is, "probably not." The answer to the second question is, "he most certainly can, and has already done so." I suspect that the best way for you to shut him down, and regain your own peace of mind, is to hire a lawyer to represent you and handle your ex's requests. If you cannot afford to hire a lawyer, try contacting Legal Aid (www.legalaidnc.org) to ask if they could represent you free of charge.
Whether any of the four issues you mention have merit depends on a lot of facts. I'm not in a position to predict what decision a court would make.
Your ex has the right to file the proper forms with the proper court in order to get his claims before the judge. If he hasn't put all the right elements in his complaint, you can ask the court to throw it out. Once he gets the case or motion in court, he has the right to discover various sorts of information from you, but some types of information are off limits. There are some limits to the quantity of information he can request, and the court may be willing, if you ask, to deny him access to some very private or sensitive information.
A competent attorney should be able to quickly identify if there are any defects in your ex's court papers, or if the case can be dismissed. Having a lawyer respond to your ex's requests may also scare him a little, or, at least, put him on his best behavior. And your lawyer will know what types of information you do not have to divulge, and what steps can be taken to protect it.
Good luck with your case.
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