Hello, you shouldn t be so worried since you were examined in the hospital. If you had something serious, I m sure the colleague who examined you, would have told you so. You can take acetaminophen for the discomfort. Do not take it only when you have the fever but on a regular basis (every 4-6 hours) for as long as you feel sick. You haven t given enough data to suggest a possible diagnosis. Most low grade fever cases (like yours) are attributed to viral infections. Fortunately masturbation does not cause fever or our planet would had been a really hot place! I also suggest you consult your doctor for the fever in case you haven t seen signs of improvement already. Since you mentioned no other specific symptoms or signs suggesting any diagnosis would be risky. I hope you get well!