Body heat. feels like a fever. Seconds.

I have been going through a problem since january.it started with burning sensations all over by back neck n back of the arms.i referred a doctor who gave me some allergic medicines.After 7 to 8 days..some random pains started occuring all over my body.pains were more like nerve pain to me..which used to last 10 to 30 seconds.got b12 done..it came fine.In feb i consulted a neorosurgeon.he asked to get my mri done.in the mri a leison was detected in mu left lobe of the neck.then went for a fnac from two hospitals.one of the reports said hashimotos thyrodities benestha category 2 and pther report said adenimotos goitre.i was told for a followup for one year.endocronologist said my pains are not at all related to this leison.i switched to yoga and prayanam.it got reduced but till june mid pains were there.got all the blood test done.everything looked fine.now since june 18 one day suddenly my body has started getting very mich heated up but thermometer does not show any temp.