There is no such things as "the last record", only the last record of your view on the table. What I mean is the last record depends on how the table rows are retrieved and what sorting and filtering has taken place. What you need is a way to identify the last added record using a field.
For instance, in the append query you can have a field which records the date/time that the record was added. Now you can add an ORDER BY clause to ensure that the record added most recently will always be the last in the table.