How loud was your tinnitus compared to everyday noises? Mine can be masked by urban environment during the day, and my doctor never used a stethoscope on me yet.
As they get louder, I can easily hear them over tinnitus. The cicada sound itself is interesting. Distant ones combine to make a sort of steady hum, almost a whistling noise. Ones that are close by make a distinctive sharp wavering buzzing noise. The sounds are distinctive and there doesn't seem to be any in between.
I have the same. So much so that I now rely on its intensity when I wake up to gauge how well I slept at night.