Go back to your hotel room. It's virtually impossible to get comfortable in a public bathroom.
Step2
On the way back to your hotel, buy bottled water, re-hydrating salts, pain killers, and bread (bread helps "plug" diarrhea).
Step3
Tell a friend or someone at your hotel reception that you are not feeling well and may need their help. Inform them of any medication that you have taken or will take, as well as any allergies. This will be helpful if you lose consciousness and they call a doctor.
Step4
Put a trash bin or bucket next to your bed, just in case you don't make it to the bathroom.
Step5
Lie down and rest.
Step6
If your sickness persists for more than three days, or if it involves blood, see a doctor.
Tips & Warnings
Drink plenty of water, avoid dairy products, and do not attempt to accomplish anything physically taxing.