Programming with PHP & jQuery

I'm programming a system and I want to know if this is the correct way or if there are a better way to do it.

Container:

I have more fields but I only added one to show you the container.

<form method="post" class="form-horizontal" onsubmit="return submitForm();" role="form" id="div-studentStatus">                     
    <div class="form-group">
        <label class="col-sm-3 control-label">Status:</label>
        <div class="col-sm-5 text-primary" id="div-studentStatus">
            <input type="hidden" value="<?php echo  $_POST['id']; ?>" id="studentId">
            <select class='form-control input-sm'  id="studentStatus">
                <option value="1">Activo</option>
                <option value="0">Inactivo</option>
            </select>
        </div>
        <div class="col-sm-3" align="center"><button type="button" class="btn btn-success btn-block btn-sm" id="statusSaveButton">Guardar</button></div>                                    
        <div class="col-sm-1">&nbsp;</div>
    </div>                                                      
</form> 

JS:

When the user click on statusSaveButton, I append a confirmation button (statusSaveButtonYes and statusSaveButtonNo). I only add the action if the user clicks on YES.

$(document).on('click','#statusSaveButton',function() {
    $('#studentStatus').attr('disabled', 'disabled');
    $('#statusSaveButton').prop('disabled', true);
    var studentStatus = $("#studentStatus").val();
    if ($("#studentStatusConfirm").length) {
        $("#studentStatusConfirm").html('<div class="col-sm-12">Are you sure you want to modify the record?&nbsp;&nbsp;<button type="button" class="btn btn-success btn-xs" id="statusSaveButtonYes" style="width:30px">Yes</button>&nbsp;&nbsp;<button type="button" class="btn btn-danger btn-xs" id="statusSaveButtonNo" style="width:30px">No</button></div>');
        $("#studentStatusConfirm").show();
    } else {
        $("#div-studentStatus").append('<div class="form-group" id="studentStatusConfirm"><div class="col-sm-12">¿Estas seguro que deseas modificar el status del alumno?&nbsp;&nbsp;<button type="button" class="btn btn-success btn-xs" id="statusSaveButtonYes" style="width:30px">Si</button>&nbsp;&nbsp;<button type="button" class="btn btn-danger btn-xs" id="statusSaveButtonNo" style="width:30px">No</button></div></div>');      
    }
}); 
$(document).on('click','#statusSaveButtonYes',function() {
    var studentId = $("#studentId").val();
    var studentStatus = $("#studentStatus").val();  
    $.post("content/studentsAction.php", {action:"editStudentStatus", studentId:studentId, studentStatus:studentStatus}, function(data){
        if (data != "Successful") {
            $("#studentStatusConfirm").html('<div class="col-sm-12 text-danger">'+data+'</div>');
            $("#statusSaveButtons").show();
            $('#studentStatus').removeAttr('disabled');
            $('#statusSaveButton').prop('disabled', false);             
        } else {
            $("#studentStatusConfirm").html('<div class="col-sm-12 text-success">Success.</div>');
            $("#statusSaveButtons").show();
            $('#studentStatus').removeAttr('disabled');
            $('#statusSaveButton').prop('disabled', false);
        }
    });
}); 

Action (content/studentsAction.php):

I have 8 different actions in this page (I only add one): change status, change level, change name, etc. I control the action with the $_POST["action"] variable.

<?php
$regex_studentId = '/^[0-9]{1,12}$/';
$regex_studentStatus = '/^[01]{1}$/';
if (isset($_POST["action"])) {
    if ($_POST["action"] == "editStudentStatus") {
        if ((isset($_POST["studentId"])) and (isset($_POST["studentStatus"]))) {
            if ((preg_match($regex_studentId, $_POST["studentId"])) and (preg_match($regex_studentStatus, $_POST["studentStatus"]))) {
                $updateStudentStatus = updateStudentStatus($_POST["studentId"],$_POST["studentStatus"]);
                if ($updateStudentStatus) {
                    echo "Successful";
                } else {
                    echo "Error.";
                }
            } else {
                echo "Error.";
            }
        } else {
            echo "Error.";
        }
} else {
    echo "Error.";
}
?>

Database:

function updateStudentStatus($studentId,$studentStatus) {
    include ("./businesslogic/dbconnection/cfg.php");
    $db = new PDO('mysql:host='.$server.';dbname='.$db,$db_user,$db_password);
    $string = "update students set student_status = :studentStatus where student_id = :studentId";
    $sql = $db->prepare($string);
    $sql->bindParam(':studentId',$studentId);
    $sql->bindParam(':studentStatus',$studentStatus);   
    if ($sql->execute()) {
        $db = null;
        return TRUE;
    } else {
        $db = null;
        return FALSE;
    }
}