High blood sugar after meals

the beginning of April I was diagnosed with a severe UTI and sepsis. I had a 4 day stay at the hospital, and 12 days of antibiotics orally after discharge. I am a Type II diabetic with a typical 2 hour PP of 120-140, with oral meds. Since the hospital stay my doctor has added insulin after meal on a sliding scale, based on my sugar when I check it 2 hours pp. I was/am expecting this to be a temporary thing, but I am having a great deal of difficulty getting my glucose under 160-170 after meals. I am following my dies closely, even eating less than I am permitted, but still having readings that are high for me. Can you give me any idea of what is going on? I do have a follow-up later this month with my PCP. Thanks, Deb