Talk to Gastroenterologist on Abdominal Fullness With Abdominal Pain

From past 3 or 4 months i m experiencing abdominal fullness and abdominal pain..after i ate something blaoting starts and then alot of gas ..i pass stool with difficulty now with hard stools then followed by liquid stool with its color changed then normal..my life is no more normal nd i m n very stress...plz help me or guide me what to do..m using metoclopromide nd pepzyme but no good improvment!!