Amniotic fluid levels - 20 weeks

What was everyone’s fluid levels at 20 weeks? I’ve had a lot of watery discharge but tested negative for fluid. 2 days after testing negative I went in for my anatomy scan and my level was only 3.3. The ultrasound tech told me it should be above 5 but when I brought it to my doctors attention I was told that “fluid is the babies urine and that it will fluctuate”. Just wondering if anyone else has had similar levels at 20 weeks. Thoughts on if I should be concerned/get a second opinion?