Hi. Welcome to HEALTHCARE MAGIC.. I have gone through your query and can understand your concerns.. As per your complain jaw pain and difficulty in opening mouth does not seems to be due to sore throat and flu and can be commonly related to two conditions like: 1. Temporomandibular joint disorder which occurs due to disorders associated with the jaw joint and it can lead to pain in jaw, ear and the temple region that is side of head.. 2.It can also be due to swollen gum flap around wisdom tooth known as Pericoronitis, in case if there is erupting wisdom tooth, it can also lead to pain in jaw radiating to ear, side of head and at times can lead to pain and soreness in throat and swelling in the region can lead to pain and difficulty in mouth opening.. You should consult an Oral Physician and get evaluated and treatment can be planned depending on final diagnosis.. The Physician may advise you to get a full mouth x ray [OPG] done as well as in case of pericoronitis an x ray [IOPA] of the wisdom tooth can be helpful in making diagnosis.. As of now you can take painkiller like Ibuprofen for pain relief.. Hope this information helps.. If you find the answer helpful please give me a Five Star Review and click on found the answer helpful as a token of appreciation.. Thanks and regards.. Dr.Honey Nandwani Arora..