Cryptosporidium and Giardia both take about two weeks to develop a full set of symptoms. Food poisoning, in the medically accepted sense, is caused by toxins that develop from bacteria in food. It can develop within minutes of eating but usually takes a few hours for symptoms to appear. I'm sure that what you experienced was not Cryptosporidium or Giardia. I suspect it was either food poisoning or something you picked up earlier finally developing while you were on the trip.