1year post gastric sleeve surgery, vomited blood. Should I be concerned? Also UC patiant

I have underwent the gastric sleeve surgery on 21st may 2016 (dropped from 500 lbs to 160 lbs). Im also diagnosed with ulcerative colitis, and I recently i had a flare up, and was admitted to the hospital for treatment, and now im on a high dosage of cortisol, this medicine is known to maximize your appatite, but this is my first time to take it after surgery, i ate alot compared to what i normaly eat, I vomited, but there was blood streaks with my vomit . Now im worried, dont feel pain though.