Class Diagram if the relationships are correct

I created a Class Diagram. This is just a concept but i want to know if the relationship are correct and if i fully understand it.

MainClass

• CreateClassA(); creates ClassA with new ClassA();
• CreateClassB(); creates ClassB with new ClassB();
• getConcreteFromCreator(); get the concrete class from creator. The creator has a switch case to determine which concrete class to return.
  • After the class is returned then call it for example (Abstract callConcrete = new ConreateA())
• CreateClassAA(); creates ClassAA with Interface createClassAA = new ClassAA();

ClassAA

• ClassAA creates classBB with new ClassBB();

Relationship from ClassAA to ClassBB is this suppose to be a composition? since the classAA is the creator of ClassBB and it depends on it from existing The relation between InterfaceAA and ClassAA is realization. I wasn't able to draw the line using NClass diagram.

Class Diagram