I'm In Tanzania, Originally From Ireland, I Have Been Here

I'm in Tanzania, originally from Ireland, I have been here two weeks. Yesterday morning I was throwing up and had slight cramps in my stomach. It went away after a few hours and I thought I was better. At about 4 this morning I started having terrible stomach cramps followed by diarriah followed by throwing up which would ease the cramps for a bit, then they would start again and the cycle would continue. What's wrong with me please help