Don't drink lots of fluids nor fiber, Stung some when defecating earlier. No blood on stool or tp. Didn't hurt after. What could it be? Will it hurt again?

Possibly. if stools are hard and if it is causing a hemorrhoid .You need to increase fluids (water preferably and a diet wit some fiber will help.
Well. This could be normal. Nothing to Panic. And why would you not drink water or have at least 15 grams of fiber a day... it is so healthy!!!