Cold night time drenching sweats last two nights since running my first half marathon. no nausea, fever. clear urine. stool fine. just knee pain. ?

Night Sweats : Naturally, night sweats are worrisome and sometimes indicate an infection or chronic disease as the underlying cause. Given the proximity to what had to be a stressful event for your body metabolism, and given that you describe no other systemic signs and symtoms such as fever, cough, rash, etc., the likelihood is that they will subside. If not, seek a consultation with your health care provider.