What Causes Bloating Of Abdomen Along With Severe Constipation?

I am a 52 year old female. My stomach is bulging and firm just below the rib cage. I often get pain in the back. I feel full most of the time and it feels like I will vomit but I don t. Without a fiber supplement, I cant pass stool. If I press on my bulge, I get headaches. I also have moderate blood in my stool.