Unfortunately, this is the type of issue that needs looked at much sooner than later. The symptoms of intestinal parasite infection can be non-specific so despite your travel to South America, there is really no way to know what you have without additional testing. Travel to the developing world can be a risk factor for contracting many illness including intestinal parasites. Once such culprit is Giardia. Giardia is a single cell parasite which can hangs out in infected water supplies or infected food. About 2 weeks after the initial infection patients tend to report very water diarrhea
, nausea and vomiting (i.e. both ends), severe abdominal pain and excess gas. If your GI symptoms don't quite fit with this description, you may have caught something else. Other parasite such as helminths (worms) can have more vague abdominal symptoms (a little pain, indigestion etc). These can still by harmful to you by causing intestinal bleeding and vitamin deficiencies. I would suggest further evaluation first by your primary care physician
and then perhaps by and infectious disease specialist
. Bring with you information such as the color, quantity, and event the smell of your stools. Make sure to write down exactly where you were and what you ate while there. Good luck.