Hard time discharging stools

Hi im 20 now. I just want to know why is is that my bowel movement has turned into something weird. Its one week now since this happened. We went to a party last sunday and i just freely ate everything and i got this 1 plate of pork with fats (i like fats) and i forgot to drink plenty of water after that meal. So the next day, im starting to feel weird, like having a diarrhea and constipated. Even if i eat much food, i still don't feel like discharging my bowel. 2 days after the mysterious party, i still can't feel that there's a bowel to be discharged. Why is that? Then the 3rd day i took one tablet of *Dulcolax* the 4th day i discharged a normal bowel movement then the fifth day nothing happened again. 6th day was normal and now 7th day im starting to have a diarrhea again. what was happening to me? Is it normal to discharge a watery stool with less solid waste at the same time? Thanks!!!!!!