any trouble in Tunis because customs does not want to let u out, call the US embassy as u r now a US citizen
and always keep a copy of the US passport and NOTE they cant take it from u / they can look at in / look in their system/ take u to customs for baggage check
but they can't keep u from leaving the country unless u have a warrant out for your arrest in Tunisia
and i would think since u had to provide a clean criminal report, that won't be an issue