I Have For The Last Three Days Experienced Occasional Mild

I have for the last three days experienced occasional mild stabbing pain in my right lower abdomen. This happens about four or five times a day and only with slight movements like sitting down, standing up, turning over in bed. However, I did also experience the same thing when I tried to swim today and it did not happen when I quit kicking my legs. The pain only lasts a second or two and then I'm fine. I've had kind of a distended stomach lately and have had more gas than usual. I've been taking large amounts of a magnesium and calcium supplement called Natural Calm at night and it seems the distended stomach coincides with this.