Post Massage Pain

Recently, I had a one-hour pressure point massage.  For three days afterwards, I felt bruised from my neck to my lower back.  Overall, I believe the massage did a great deal of good.  But a couple of days after the massage, I started to feel cramping in my lower back, thighs and buttocks.  The cramping felt like it could be constipation, however, this does not seem to be a problem.  My bowel movements have not been difficult, hard or infrequent.  In fact, I'm probably going more now than I did before the massage.  Could it be that the massage released a high amount of toxins and my colin is trying to eliminate these toxins?  Has anyone had similar symptoms after a massage?