I had coffee this morning with milk and sugar. and now my stomach is hurting, i have diaherra, i feel like theres a lump in the left side of my throat?

May be unrelated: Not sure this is due to coffee. May have a virus causing the symptoms. If symptoms persists would go to urgent care center or your doctor for evaluation.

Coincidence?: In predisposed individuals, caffeine can trigger intestinal peristalsis and, hence, stomach ache and diarrhea. However, if this is the first time this has happened after your morning cup of coffee, then the two are probably unrelated. Also, unless the coffee was VERY hot, I don't see any connection between the coffee & the lump in your throat.