HCG levels lower..

Irah

So the Wednesday before last.. I got a faint positive test. That following Friday July 31st, I got a strong positive and went in to get HCG levels tested. They came back at 111 which seemed pretty good for being about 4 weeks. I went back yesterday which is a week to get HCG levels again and now they are at 106 at 5 weeks. I assume this is a bad sign but also odd that it’s barely moved higher or lower. Anyone have similar experience?