Deshabilitar múltiples envíos de formulario con Vanilla JavaScript
var form = document.getElementById('formID');
var submitButton = document.getElementById('submitID');
form.addEventListener('submit', function() {
// Disable the submit button
submitButton.setAttribute('disabled', 'disabled');
// Change the "Submit" text
submitButton.value = 'Please wait...';
}, false);
BluSilva