Hi there ~
I understand your concerns. High temperature along with head, back and neck pain
with a sore throat
sound like a viral infection that should be easily treated with adequate rest, plenty of fluids and also symptomatic treatment for the aches and pains. I hope you are doing it enough and if you continue to experience difficulty please consult an ER doctor as soon as possible if your regular doctor's appointment cannot wait.
I hope this helps. Take care and have a lovely day!