Triple test confusion

I did the quad test at 16.1w according to LMP, and my result came back with a 1:227 risk for Down's. The MoM values for AFP was 0.53 (17.8 ng/mL), uE3 was 0.79 ( 2.16 ng/mL), hCG was 0.82 ( 21.4 IU/mL), inhibinA was 2.26 ( 427.0 pg/mL). My age at term would be about 31 years.

I repeated the triple screen at 17.4 weeks according to LMP (though U/S that day gave a GA of 18w2d), and this time my risk was calculated to be 1:8000. The MoM values for  AFP was 0.48 (27.5 ng/mL), uE3 was 4.13 (5.6 ng/mL), and hCG was 0.94 (23.2 IU/mL). Note that this was done in a different lab.

I would like to add that I had also done a first trimester NT plus PAPPA blood screen, which gave me a down's risk of < 1:5000. The MoM for NT was 0.8, and the PAPPA was 1.73.

Additionally my level II U/S had no markers and everything looked absolutely normal. My question is based on the way my uE3 changed between the 2 maternal serum tests, I think the risk changed significantly. Does this change in uE3 seem like what would be expected at that stage in pregnancy? How much should I worry about this first multiple marker result though it seems like a false positive?

I declined the amnio but now am going back and forth wondering if that was the right decision. I am looking for someone to look at my numbers closely, and see if they seem possible for an unaffected pregnancy. Just to add, I am carrying a female fetus if that adds any more information and my racial origin is Asian.

I really look forward to an answer from one of the doctors since I think I am running out of time for an amnio.

Thanks!