While I do not love the word “normal,” this is very common and is something I would expect in many cases.
We develop ways to survive particular circumstances as children. As adults, some of those same methods become maladaptive. They interfere with relationships or stand between us and our goals.
A person may come to therapy because they recognize significant problems in their life. Together, the therapist and patient begin to understand the issues connected with those patterns and with a distorted sense of self.
As old defenses and coping mechanisms are questioned, a person can temporarily feel less stable. The familiar facade may no longer work, while a new sense of identity and healthier ways of coping have not yet become solid.
This vulnerable period can feel like things have gotten worse, even when it is a sign of movement. It can offer the opportunity to develop a sense of self based more on reality and on who you truly are, rather than one imposed by childhood circumstances.