UTI with side pain and fever?

I’ve had UTI symptoms for a couple weeks (urgency to pee, constant feelings of having to pee), I’ve taken cranberry pills and juice but it hasn’t gone away. Then about 5 days ago I started experiencing pain in my right side and back under my rib cage. I told my sister in law who’s a doctor and she prescribed me an antibiotic. The day before I started the antibiotic I began experiencing feverish symptoms as well. I’ve only been taking the antibiotic for about 24 hours but the pain consists and my fever has been on and off. Could this be more than a UTI?