Nausea going away.

Both of the previous pregnancies I was extremely sick and vomiting till about 16 weeks. I am now 8.5 weeks along and nausea has been bad for the last 2 weeks but all the sudden over the last 3 days it's much much better. This never happened with my two previous pregnancies. I'm getting very scared that maybe my levels are dropping and I could have a miscarriage. Anyone else have this kind of drop and baby was still fine??