How can I validate from jquery a form that is repeated several times within a while cycle?

I am trying to validate a form that has inputs (radio type) that are repeated through a while cycle while data is being found in the db.

I can not validate these dynamic forms using jQuery because if I let it validate only the input that is checked; When you choose any input you would already fulfill the condition, but I need to validate several input that are inside a different form.

How could I validate that when there is no option selected in any of the forms, it tells me that there are still some options to be selected?

Here is the code:.

PHP

$contacform = 0;

while ($row = mysql_fetch_array($resultados)) {

    echo '<div class="con">';
        echo '<p id="p">'.$contacform.'</p>';
    echo '</div>';

    echo '<form id="myformid" data-form="'.$contacform.'"align="center">
        <h2><strong>'.utf8_encode($row['pregunta']).'</strong></h2>
        <br>
        <label>'.$row['opcion1'].'</label>
        <input type="radio" name="check" id="check" value="1" required />
        <input type="hidden" name="checkd" value="'.$row['id_pregunta'].'" checked/>
        <br>
        <label>'.$row['opcion2'].'</label>
        <input type="radio" name="check" id="check" value="2" required />
        <br>
        <label>'.$row['opcion3'].'</label>
        <input type="radio" name="check" id="check" value="3" required />
        <br>
        <label>'.$row['opcion4'].'</label>
        <input type="radio" name="check" id="check" value="4" required />
        <br>
    </form>';

    $contacform += 1; 
}

echo '<div class="text-center">';
echo '<br>';
echo '<button class="btn btn-primary text-center enviartest">Enviar</button>';
echo '</div>';

JavaScript

$('.enviartest').click(function(){
    var selected = [];
    var selectedid = [];
    var my = [];

    /* Recorro el contador que se encuentra  en la etiqueta p dentro del div  con class con */
    $('.con p').each(function(){
        // alert($(this).attr('id'));

        /* obtengo lo que tiene  el  texto  de la  etiqueta p */
        var o = $(this).text();

        my.push($(this).attr('data-form'));;

        var definit = $('#myformid'+o+'input[name=check]');

        /*intento validar que cuando  seleccione   el formulario  numero  tal   y este  chequeado  el input con name  check  que es array me  mande un mensaje*/
        if ($('#myformid '+o+'input[name=check]:checked').is(':checked')) {
            alert('hola soy un cero');
        }else{
            alert('elije algo');
            alert(o);
        }

    });

    /*los input  que tengan  name  check y esten  chequeados  checked*/
    $('input[name=check]:checked').each(function(){
        selected.push($(this).val());
    }); 

    /*los input  que tengan  name  check y esten  chequeados  checked*/
    $('input[name=checkd]').each(function(){
        selectedid.push($(this).val());
    });

});