For a single property, that says nothing at all.
§13 does not deal with development plans as such, but specifically with the applicability of the simplified procedure when drawing them up. In §13a it is then explained if and when the principles of §13 are to be applied to the case of densification. This concerns building plots that arise by splitting off rear gardens from such plots, which themselves have been continuously developed at the front ends according to §34. § 13b, in turn, explains the purpose of § 13a is also to be applied to a similar group of cases, namely to areas that, unlike in § 13a, arise not in the "core" of already developed areas, but "beside" them.
In principle, § 13b can therefore indeed cover your property. But not individually. You will regularly have to wait until the municipality intends to issue a development plan for the district in which your property is located on the basis of § 13b. If their hunger for new building land has been satisfied beforehand, they will not do this anytime soon. Alternatively, you can suggest changing the boundary of the valid area of the neighboring development plan so that your property is included as well. In practice, this requires a good relationship with the relevant authorities in the council and/or administration – including not being on bad terms with their friends.