Your pain can be caused by kidney/ureter
stones (or even infection). Looks like you haven't had a urine test performed (however it not always shows a signs of stone in urine). Kidney stones may cause a state called paralytic ileus
what means that some irritating factor (inflammation in any abdominal area including kidney/ureter) stops proper function of intestines so the contents of intestines stops moving forward. That is why there is a lot of gas, nausea and stomach pain. It is advisable for you to have urine tests, blood tests (your high blood pressure
may be a sign of severe infection), abdomen ultrasound
(renal blockage can cause hydronephrosis
what is urgent). Your symptoms may also mean that there is some other than kidney reason of ileus.
Abdomen X-ray should be repeated and if there is a suspicion of ileus, contrast examination of intestines should be done.
Hope this will help