Reflection and introspection are two different words, though there can be some similarities between them. The word reflection means the act of reflecting on something or the state of being reflected. At times, when you reflect on certain things in your life, you tend to be thinking about some things you are doing that you need to improve on and also those things you need to stop doing.
Also, you can also reflect on some things that are not actually about you. In short, it means the act of giving something a deep thought or thinking seriously about something. On the other hand, introspection can be referred to as a psychological process that makes someone look inward. This is simply a process of self-examination of one's feelings and thoughts. When you introspect, you are self-evaluating yourself. When you compare the two processes, introspection is deeper than reflection.