Blood appeared in my urine - The Second Story

The reason I visited the nephrology department first was that I had heard that in order to go to a general hospital, I needed a referral from a nephrologist.

The doctor, who was very kind, asked me a few questions:
My recent lifestyle, whether I had any other health issues, and so on.
I mentioned that I had been exercising a bit more recently, but not to the point of overexertion (I had heard that strenuous exercise could cause blood in the urine due to rhabdomyolysis).
I also mentioned that I had been consistently taking vitamin C for about 10 years, and that I had recently started taking about 10 spirulina tablets after dinner.

I suspected that the spirulina might be the cause, but the doctor told me that such supplements typically do not cause blood in the urine.

So, I underwent an X-ray, urine test, and blood test.
The X-ray results were available immediately, and the doctor said there didn't seem to be any major issues based on the X-ray.
He advised me to come back in a few days for the results of the urine and blood tests.

As anyone who has had to wait for medical test results knows, those few days were truly nerve-wracking.
What if it's something serious? Will I be able to see my child grow up? I couldn't help but cry.
To make matters worse, my wife and child were away on a trip, which only increased my anxiety.

Of course, I stopped taking any supplements from the day of the test.
The doctor also advised me to avoid exercise for the time being, so I refrained from it entirely.
During those few days, whenever I went to the bathroom, I continued to see blood in my urine. It wasn't as bad as the first time, but I could still see the blood mixed in, and it was still difficult to urinate.

After about three days, I received a call saying that the results of the urine and blood tests were ready, so I went back to the hospital.
The doctor said that there was blood in the urine, but that the other test results showed no abnormalities, so the cause was unclear.

At that point, I was desperate to find the exact cause and get proper treatment, so I asked for a referral to a general hospital.
(Later, I learned that the hospital I went to next did not require a referral at all.)

I looked up a few places and decided to visit the Good Kang-an Hospital near my home.