Can you take morphine if you have an ulcer?

Last night, after 3 months of pain, I was diagnosed with an infection in my stomach and an ulcer. Sadly none of the drugs I was given was for pain. I'm in excruciating pain(more so than I have been in these past months) and was wondering if I can take some leftover morphine? I had it from a previous hospital visit, so it is mine. I am taking 4 amoxicillin, 2 clarithromycin and 2 prilosec a day as instructed by my doctor, so I dont know if morphine will affect these at all.