My lower abdomen sticks out a little (btwn hip bones and naval) is this normal? Not constipated, drink lots of water, exercise daily

Yes. That is probably normal . Some people has slightly different abdominal wall muscles or have a different curvature to their back that makes their lower abdomen protrude slightly. If you are otherwise healthy, no need to worry.
It's fat or flabby. Muscles. I won't worry unless there's accompanying symptoms like abdominal pain, nausea, vomiting, diarrhea , constipation, urination problem etc. Do some stretching or toning exercises. Take care!