I Have Severe Stomach Pain Center And Under Belly Button..

I have severe stomach pain Center and under belly button.. I have rectum blessing quite often. I go from diarrhea to complete constipation. Now I recently started having lower back pain (perhaps from constipation) I suffer from fatigue and itchy skin mostly on back, armpits and stomach.. I feel something is not right in my stomach as I can feel extremely full, bloated then feel hungry quickly! I also vomit mostly in the mornings. Any thoughts?