Stuttering SLP here, resurgence of [recovered] stuttering is exceedingly rare--in fact unheard of except in cases of neurological trauma. I'm suspect of a psychogenic cause of stuttering, it also being exceedingly rare. I do recommend seeing a neurologist to rule out subtle neurological damage. Neurogenic stuttering is caused by infarcts to many isolated regions of gray matter. I also recommend seeing a SLP, there are ways to differentially diagnose developmental stuttering from neurogenic stuttering. (In your case I'd look for a SLP with the specialty certificate in stuttering).