I m 15 weeks pregnant. I get all day headaches/migraines often. I noticed they seem to coincide right before I have a large bowel movement, followed by burning in my rectum, then a liquid green acidy bowel movement. The headache/migraine remains for the rest of the day but subsides once I wake up in the morning. I drink water constantly through out the day so I don t believe the issue is hydration. Just recently this issue occurred and I noticed the next day my stool was very pale and the water was cloudy. There was still a burning feeling. I ve had issue before I was pregnant but the headaches/migraines are new.