Since last 3 days I was experiencing dizziness and headaches and was unable to pass proper stool. After sitting for a long time in bathroom and with pressure pebble size stool get passed. I don't know what's wrong, i used to go atleast 3 times a day with normal stool before. Please tell me what to do. I drink water the first thing after waking up in the morning, I also took Pan-D tablet but nothing happend. Should I be worried?