Acute infection in the root canal area can give rise to severe pain, which radiates to the whole jaw, ear, head & sometimes the neck. However, in your case the offending tooth has now been extracted. Without seeing your x-rays & without clinical examination all I can say is that there could be two reasons for the pain to persist.
1. Coincident cervical spondylosis which has not been investigated / detected.
2. Localised osteitis (inflammation of the bone) in the area of that tooth. Of course a definite diagnosis can only be made after a detailed clinical examination.