Looking for advice about possible PPROM

Here's my backstory:  I'm currently 22w3d w/ pregnancy #3, but this would be my first take-home baby.  Both losses were early m/c BO.  About 2 weeks ago I started noticing a bit more wetness in my underwear and decided it was probably nothing.  Then a few days after that I developed some UTI symptoms so I went in to have those checked out (which ended up being a false alarm).  I forgot about the wetness, but then the next day felt like I should have asked, so I called and they brought me back in for exam.  I saw the NP and she did a fern test, which came back negative, and sent me for an u/s, which showed my fluid as low normal.  They scheduled a repeat u/s w/ orders to drink a lot and rest during that week wait.  I ended up being too concerned to wait a whole week, so went back 5 days later and had the repeat u/s.  The fluid had increased a bit and the u/s tech (who had done the previous scan also) was quite pleased with it.  I got to see my reg OB this time and he was totally not concerned, even though I mentioned that I was still having this sort of "leaking" going on.  He chalked it up to reg pg discharge.  So that was about a week ago, but I just can't seem to shake this feeling that I am leaking amniotic fluid.  I don't leak constantly.  I notice more when I sleep than when I'm up and moving around.  (Which makes me paranoid b/c you hear all these stories around the net that the baby is plugging your cervix when you are upright and not when you lay down, so if you leak while lying down it's more likely to be AF.)