How alter onclick event of code for first time login

I have the following code in an onclick event of a login form.  But I need to alter it so that in the event the user is logging in for the first time they will be taken to a separate form to enter their new login of choice.  Then after they have entered their new login be taken back to the original form to continue.  How do I alter the following code?

'Check to see if data is entered into the Password combo box
    If IsNull(Me.txtPassword) Or Me.txtPassword = "" Then
            MsgBox "You must enter a Password.", vbOKOnly, "Required Data"
            Me.txtPassword.SetFocus
        Exit Sub
    End If
   
'Check value of password in tblEmployees to see if this matches value chosen in combo box
    If Me.txtPassword.Value = DLookup("Password", "tblEmployees", "[EmployeeID]=" & Me.cboName.Value) Then
       
        myempid = Me.cboName.Value

    Dim rs As DAO.Recordset
    Set rs = CurrentDb.OpenRecordset("LOCALtblLogin")
            rs.AddNew
            rs!FullName = Me.txtFullName
            rs!EmployeeID = Me.txtLoginID
            rs!DateTime = Now()
            rs!SecurityLevel = Me.txtSecurityLevel
            rs.Update
       
'Close logon form and open splash screen
    DoCmd.Close acForm, "frmLogin", acSaveNo
    DoCmd.OpenForm "frmMainMenu"
    Else
        MsgBox "Password Invalid. Please Try Again", vbCritical + vbOKOnly, "Invalid Entry!"
        Me.txtPassword.SetFocus
    End If

'If User Enters incorrect password 3 times database will shutdown
    intLogonAttempts = intLogonAttempts + 1
    If intLogonAttempts > 3 Then
        MsgBox "You do not have access to this database. Please contact your system administrator.", vbCritical, "Restricted Access!"
        Application.Quit
    End If
           
    DoCmd.Close
   
    DoCmd.OpenForm "frmMainMenu"