Hello I started with diarrhea last Tuesday. It is water
You need medical attention...
I went through your course of symptoms. You have been suffering with recurring loose stools since last tuesday. Now, you developed abdominal cramps. I assume the cramps is located in the lower abdomen.
These symptoms suggest colitis / gastroenteritis. It could be bacterial in nature. Stool analysis will help us identifying the cause. I understand you have an important event today. But I am not sure the symptoms can be treated with over the counter available options. I will recommend you visit your doctor / urgent care clinic / ER. Antibiotic like ofloxacin might help you along with a probiotic agent. Imodium should be continued under cover of antibiotics.
Until then stay hydrated with fluids / oral rehydration fluids.
Hope this helps. Let me know if you need clarifications.