What Causes Sharp Pain In The Lower Abdomen Along With Dizziness?

Hi,

I have been having lower abdominal pain on the left side. It's not sharp or stabbing, mostly achy and dull. I've had this feeling for many months now. I had an issue with constipation for an entire month, xrays showed that I was severely impacted. Later on, ultra sounds for the abdominal and pelvic region showed no abnormalities. But today and yesterday the same pain came back. It feels like the pain moves a bit but returns back to the same spot just inside of the pelvic bone. I am dizzy and lightheaded (for two days now) and have a fishbowl effect with my vision. I just checked my blood pressure and it shows 124/53 and 76bpm. I'm otherwise healthy, 26 female, small build. Should I be concerned?