Try this:
$page_id = 'YOUR ID';
$access_token = 'YOUR ACCESS TOKEN';
$json_object = @file_get_contents('https://api.instagram.com/v1/users/' . $page_id .
'/media/recent/?access_token=' . $access_token . '&count=1');
$indata = json_decode($json_object);
echo $indata->data[0]->images->low_resolution->url // for low res
echo $indata->data[0]->images->thumbnail->url; //for thumbnail
echo $indata->data[0]->images->standard_resolution->url; //for standard res
echo $indata->data[0]->caption->text; //for caption
Embedding the whole post may be a solution:
$json_post = @file_get_contents('https://api.instagram.com/oembed/?url=' . $indata->data[0]->link);
$oembed = json_decode($json_post, true);
echo $oembed['html'];
Good luck!