Help! Pain in left side due to constipation

I have IBS.  I went to the doctor today because I had pain on my left side-lower abdomen.  This was after two days of excessive gas and little if no passage of stool.  I had also changed my diet and had been eating a lot of salads.  Doctor did an x-ray and said it was not infected, and told me to get a suppository and Miralax.  I did both today.  I did have success, but I still have the pain on my left side.  Could it take a few more days to go away after taking the suppository and Miralax? 

I have the same symptoms. I don't know if it's gas distension, visceral pain or one doc explained that in that area there is a muscle that goes around the colon that is like a rubber band that stretches to open to allow passage of bowel contents. It spasms. I use Tylenol, dicyclomine or pain meds. Sometimes it lasts a couple days and it can be excruciating. I have no consistency with this either.