Serious stomach problems. Help!?

So I've been having some bad stomach problem. Last Sunday I was having constipation and I went to the doctor. She said my stomach was hard and full and got xrays. I took 5oz of magnesium citrate. I used the bathroom but didn't clear my bowels. I went back today and she told me to take 5 more oz. It still hasn't worked and my stomach is rock hard. When I push on lower right stomach it gurgles. Should I take more citrate?