Object-Oriented programming is frequently challenging for undergraduate Computer Science students, particularly in understanding abstract concepts such as encapsulation, inheritance, and polymorphism. Although the literature outlines various methods to identify potential design and coding issues in object-oriented programming through source code analysis, such as code smells and SOLID principles, few studies explore how these code-level issues relate to learning difficulties in Object-Oriented Programming. In this study, we explore the relationship of the code issue indicators with common challenges encountered during the learning of object-oriented programming. Using qualitative analysis, we identified the main categories of learning difficulties and, through a literature review, established connections between these difficulties, code smells, and violations of the SOLID principles. As a result, we developed a conceptual map that links code-related issues to specific learning challenges in Object-Oriented Programming. The model was then evaluated by an expert who applied it in the analysis of the student code to assess its relevance and applicability in educational contexts.