greetings friend, most likely if you have a medical condition called hypothyroidism
or some other kind endocrinologic condition. Simple blood work can diagnose this, and determine if you have any underlying reversible cause for her symptoms. Your muscles are sore from the shivering, not because of any underlying muscle condition. Sometimes night sweats
if they occur frequently signal a more serious condition like a leukemia
but that is probably unlikely given that he only had this twice in the last few months.cheers.