Burning In Abdomen

I had diearhea and noticed minor blood spot in stool twic also burning sensation on lower left side of abdomen near belly button. consulted gastro he prescribed tab cafspam, nexum 40mg and entamizole for 5 days. Bt now im having constipation and still feeling burning near left side of belly button.. What can be the reason? Im so worried. I had constipation problem on and off before all this.