Felt fine then 2day onset of fever increasing to 101.1/nausea/period cramps/ & diarrhea now diarrhea is better but stil what feels like period cramps ?

Gastroenteritis: This most likely a viral gastroenteritis(intestinal flu) and usually resolves in a few days without specific treatment except for Tylenol, (acetaminophen)rest, light diet, adequate fluid intake, flat ginger ale for the nausea and kaopectate to control diarrhea. See your physician if fever persists or worsens, or if persistent abdominal pain,tenderness,vomiting or black or bloody stools occur.