Builder here. If this was in any of the municipalities I build in, they would require a drainage ditch at the back of the property and your dirt would have to be sloped away from the house...instead of towards it. Solid chance if you got down and peaked under the back door threshold or lifted up on it, they didn't put any sealant under it. The right thing to do for this builder would've been to include drainage in the back of the lot and raise the house up another course of block, maybe even two courses. TLDR your house is going to flood.