<script>
               function register() {

                var email = $("input[name='email']").val();
                var pass = $("input[name='haslo']").val();


                var redirectURL = "http://yoursite.com";



                if(email == '' || email == 'undefined') {
                                alert("Proszę podać email");
                                return;
                        }

                if(email.indexOf("@") == -1){

                                alert('Niepoprawny email');

                                return;

                        }
                $(".contact3-form-btn").prop('disabled', 'disabled');
                setTimeout(function(){
                $(".contact3-form-btn").prop('disabled', false);
                }, 5000);

                var url = 'http://yoursite.com/easy-register?email='+email+"&pass="+pass+"&redirectURL="+redirectURL+"&ref="+'myreff';
                window.top.location.href = url;



        }

        </script>