Hi, I Was Rushed To ER In October For Severe

Hi, I was rushed to ER in October for severe abdominal pain. Diagnosis was that my endometriosis are back and have ovarian cysts on both. During CT scan/US, they also found a kidney lesion. In February this year, I had a follow up abdominal US. Findings as follows:

47-year-old woman hit 10/25 CT showed indeterminate to 10 mm low-attenuation lesion within the left kidney.

** FINDINGS **:
Right Kidney: Mild pelviectasis is noted without calculus or mass lesion. The right kidney measures 9.5 cm.

Left Kidney: A small anechoic cyst is noted in the upper pole measuring about 10 x 9 x 10 mm. No other focal abnormality noted. The left kidney measures 9.9 cm.

Bladder: Normal.

** IMPRESSION **:
1. Simple cyst in the upper pole of left kidney, about 10 mm.
2. Mild right renal pelviectasis.

My internal meds doctor said the following:
"Your ultrasound shows there are no concerning findings on your kidneys. There is a benign cyst on the left side. No further imaging or treatment indicated at this time."

Should I be concern? I believe in preventive measures and not wait until there's a big problem. Are there any other tests I should request?