I Have Had 2 Ultrasounds, MRI, CT-ivp And A Bladder

I have had 2 ultrasounds, MRI, CT-ivp and a bladder scope in 2016 confirming I have severe hydronephrosis and hydroureter but no blockage has ever been found. Oct. 5th of this year, my urologist performed a ureteroscopy and inserted a stent, saying that "it was difficult to insert" but no other explanation given. I went home with ciprofloxacin for 7 days. 2 days after antibiotic complete (which I've had many times before and am not allergic to in past) I developed a severe very itchy rash all over heat areas, red hot numb ears and neck and swollen eye. Went into emergency and was given 7 days Prednisone 50 mg and Benadryl. Since I'm done the Prednisone (in past 3 days) I have experienced intense burning in my lower back. I'm worried I have a stent allergy, not an antibiotic allergy. Is this possible? Should I ask to have it removed asap? I'm also worried about encrustation and other risks as the stent has been in place for 3 weeks. On top of all this, when the stent is removed, will it not collapse again and I'll be right back to where we started?