You should contact a personal injury lawyer in your area. Generally, the existence of a foreign substance in your food may constitute negligence in the preparation and serving of the food to you. In order to have a viable claim however, you must demonstrate that you have been damaged by the negligence. A small cut on the roof of your mouth, with nothing more, would not be significant enough for you to pursue. The cut will heal and you will not sustain any long terms damage, medical bills, lost wages or other compensable injury. The statement that you haven't been feeling well since is rather non-specific and could be anything. The burden will be on you as the claimant to prove that the negligence Carl's Jr. caused the injuries of which you complain.
These types of cases are hard to prove, so the medical records have to be very specific on the cause of your injuries. With that in mind, you should consult with a local personal injury attorney and discuss your options.
DISCLAIMER: David J. McCormick is licensed to practice law in the State of Wisconsin and this answer is being provided for informational purposes only because the laws of your jurisdiction may differ. This answer based on general legal principles and is not intended for the purpose of providing specific legal advice or opinions. Under no circumstances does this answer constitute the establishment of an attorney-client relationship.
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