I haven't a normal bowel movement in a few months. what could be the cause of this?

Diet: You may have had a condition that affected your bowel. In any event you should modify your diet by adding more fiber in increasing your fruit, vegetable, nuts, figs and raisins and dates. Also reduce milk and milk substances and juice. Add high fiber cereals to your breakfast.

GI and Diet eval: I recommend you get a thorough evaluation by a GI doctor (r/o ibs = irritable bowel syndrome, gluten intollerance, etc), then consider seeing someone to determine if you are having other food reactions. Be honest about all eating behaviors.