It sounds like you have a mild case of traveller's diarrhoea, which is very common and usually resolves on its own. The most important step is staying hydrated; please drink plenty of fluids and Oral Rehydration Salts (ORS). For symptomatic relief of mild cramps and diarrhoea, you can use over-the-counter generic medications like bismuth subsalicylate or loperamide. Taking probiotics can also help restore your gut balance. Avoid self-prescribing antibiotics, as they are often unnecessary for mild cases. Stick to a bland diet (bananas, rice, applesauce, toast) for now. If you develop a high fever, severe abdominal pain, or bloody stools, please consult a doctor.