Circular doubly Linked List help c++

I'm trying to implement a circular doubly linked list but I'm having issues when trying to set the previous pointer. If I set the head's previous pointer to the new node, my program hangs but when I don't it performs moderately well.

Below is the code that makes the program hang:

    head->next = newNode;
    head->prev = newNode;
    newNode->next = head 

The line newNode->next = head causes my program to hang indefinitely, what am I doing wrong with my implementation in the function?