I just wanted to say that three days ago I went through the exact same thing and worried that I was leaking amniotic fluid. I haven't been to the Dr and it has stopped but it felt exactly as you described and I wore panty liners for two days and worried myself sick. But bubs was moving hugely so I knew he was ok, and as I said it's stopped. I just thought I'd mention it as we are both around 23 weeks so it might just be one of those things that happen sometimes at this stage.
I hope it settles down for you and that the results are good when you get them back, let me know how it goes.
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