You have to use .after() method.
append method insert content to the end of each element in the set of matched elements.
after method insert content after each element in the set of matched elements.
$(document).ready(function() {
jQuery("input[title='Password']").after('<p>test</p>');
});
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<input type="text" value="secret password" maxlength="255" id="ripo" title="Password" class="ms-long ms-spellcheck-true">
Also, you can use insertAfter method in the following way.
$(document).ready(function() {
$('<p>test</p>').insertAfter($("input[title='Password']"));
});
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<input type="text" value="secret password" maxlength="255" id="ripo" title="Password" class="ms-long ms-spellcheck-true">
jQuery("input[title='Password']").val('<P>test</P>');