I have some kind of illness that is brought on by my getting hot. Headache like flu headache, body aches, fever. Have already had antibiotics, fluids at emergency and it helped for the night. However, light fever back, headache won t go away. I have another symptom which jst came up last night and that was toothache (severe) under a crown. Is it possible the tooth has been infected for a while yet no pain causing my symptoms?