A "theory" is an explanation to the happenings in the world. It is not just an assumption, instead theory is based on scientific facts. There are many theories till now to explain various things such as the evolution of the modern world, globalization etc. Hence theories are considered as a creation of new knowledge.
In the initial phases of formation of theories, most of the theories are incomplete or completing with one another. Later theories became prominent. And some theories emerged as dominant and got all the attention. This set of dominant theories is called as "Paradigm", according to Thomus Kuhn. Hence paradigm is much broader than a theory.
A paradigm is a set of beliefs and theories that a society possesses. This is the explanation for paradigm having two aspects. The first one is the "global paradigm", which is the set of beliefs and values the the whole world believes in. And there are local versions. Some societies agree with global beliefs and some do not.
World is changing at a fast pace. Hence new theories will come into existence and some theories become redundant, and some other theories will turn into false by the new theories and will be rejected if found wrong. This is called as "paradigm shift", according to Thomus Kuhn.
Paradigms acts as frameworks for the creation of new theories. Functionalism, structuralism and Marxism are some examples of paradigms. For example, Marxist paradigm looks at society as two classes - Capitalist class and working class. "Social conflict theory" is formed based on Marxist paradigm. While forming new theories, sociologists look at things in a perspective set by paradigms. And paradigm is the set of contemporary theories. Hence theories and paradigms are interconnected.