Hi.. Can understand your concern.. As per your complain it seems that due to hitting of the nerve with the injection needle there has been traumatic injury to the nerve and it is causing nerve paresthesia causing quivering of the lip and also pain.. Difficulty in opening mouth and pain near the ear and jaw can be due to infection at the site of dental treatment leading to Trismus.. It can also be due to stiffness in the muscles of the cheek.. I would suggest you to consult an Oral Physician and get evaluated and a thorough clinical evaluation and investigation like x ray can help in diagnosis and treatment can be done accordingly... As of now you can take anti-inflammatory painkiller like Ibuprofen, muscle relaxant like Chlorzoxasone and also do warm saline gargles.. Do alternate warm and cool compresses over the cheeks.. Take a soft diet and try to open the mouth wide under limits of tolerance of pain.. Hope this information helps.. Thanks and regards.. Dr.Honey Nandwani Arora.