I got it now :)
so what i did is that I added to my $getJSON a .done method.
Here is how it looks like now.
$.getJAON(Blah Blah).done(function(){
$('.triggerOnPicker').datetimepicker({
timeFormat: "hh:mm TT",
changeMonth: true,
changeYear: true,
stepMinute: 5,
beforeShowDay: $.datepicker.noWeekends,
HourMin: 5,
HourMax: 17,
minDate: 0
});
});
Thank you JAKE :) your code gave me the hint :)