Signs of a UTI turned kidney infection?

 I have a UTI and never took my meds for it bc they made me nauseous and I assumed it'd just go away since I didn't have any symptoms. however now I have a fever and extreme fatigue and nausea/upset stomach not from the medicine also mood swings(don't know if that could be related.) Also some cramping but I had that before too so idk. Could I have a kidney infection? I am going to start taking the medicine, I learned my lesson...