Constipated for 3 wks.took miralax & colace 3 days, didn't help. i've had small, hard bms but not much.took mag citrate (300ml) & had diarrhea after. no formed stools. bloating, abd. & low back pain,borbor. could this be a partial bowel obstruction?

Probably not: Doesn't sound like a typical small bowel obstruction. Its possible however. If you haven't had previous abdominal surgery, it would be very unlikely. Ask your primary if a referral to a gastroenterologist is appropriate, and ask about irritable bowel syndrome. Hope this helps!

Possibly: If you are not vomiting and are still able to pass materials by bottom, you are likely not completely obstructed. See your doctor for an exam and XRs if needed. All the best.