hi and thanks for your query, thanks for your question. A chronic dull pain to right side of the stomach most of the time is due to appendicitis, which must be excluded. Other causes like those of the ovaries, infections and renal must also be excluded. An obstetric ultrasound coupled with a good clinical evaluation and a few blood tests are usually sufficient to make a good diagnosis. the feeling you felt for w few minutes should be something transitory. repetitive episodes should warrant an consultation and evaluation by your primary care physician. I suggest you meet a gynecologist for a complete evaluation and get an ultrasound done. Thanks and best regards, Luchuo, MD.