Doubly linked list adding node at nth location

I needed help with adding a node part in my doubly linked list. I've dry run my program it seems perfect yet it crashes on adding the second or third node. I want a logical reason why is it so. Anyone? Here's my code.

class node
    {
    public:
        int data;
        node* next;
        node* previous;
    };

    class linklist
    {
    private:
        node* current;
        node* head;
        node* tail;
        int count;
        int size;

    public:
        linklist() : head(NULL), tail(NULL), size(1) {}

    void addNthNode(int Data, unsigned int position)
        {
            node* currentNew = new node;
            currentNew->data = Data;

            if (position == 1)
            {
                currentNew->next = head;
                currentNew->previous = NULL;
                head = currentNew;
                return;
            }

            node* temp1 = head;
            for (int i = 1; i < position - 1; i++)
                temp1 = temp1->next;

            node* temp2 = temp1->next;

            currentNew->previous = temp1;
            currentNew->next = temp2;
        }

    int getSizeOfList()
        {
            node* temp = head;
            while (temp->next != NULL)
            {
                temp = temp->next;
                ++size;
            }
            return size;
        }

    void main()
    {
        linklist l;

        l.addNthNode(1, 1);
        l.addNthNode(2, 2);
        l.addNthNode(3, 3);

        l.printList();
        cout << "\nSize of list : " << l.getSizeOfList() << endl << endl;

    }