I understand your frustration... Some nurses are the worst in triage, and should really change departments! I have friends that work ER and they can't believe some patients are deemed class 5 when they should be class 3, which messes up with the timely response to an accident or can turn some milder condition into life threatening.
Last time I went to the ER at my hometown hospital, I was paralysed on my right side, couldn't speak and had a hard time thinking straight. I was also 7 weeks pregnant. The people I was with thought it was a CVA, and they got me to the closest hospital, but they sent me home with a tylenol and a tap on the back, what?!
Ended up going to the City's hospital and getting checked (ECG, nerve response and such) to clear out dangerous conditions. It turned out to be a migraine, preceded by visual auras and finally ending in my right side nerves, which explained paralysis. We still scheduled a CT Scan for the end of April, to make sure everything is fine.
In the mean time, I strongly advise anyone with anything more serious than a cold to not go to that hometown hospital... I should have known better, they misdiagnosed family members before, leading to one's death. How do they still have patients is beyond me.
Good luck with your kidney infection, hopefully it goes away nicely and without repercussions. :)