I am not a doctor, either, but if your condition changed in just four hours there's a good chance the Cipro didn't bring it about. The last time I got sick in Mexico (last May), I was fine in only about four hours after an Extreme Bathroom Experience, and I didn't take anything at all. I was sick as a dog at 3AM and on the dive boat at 8AM feeling fine.... ended up getting sick as a dog while there. After taking the Cipro, I was better within four hours with little to no side effects.