Amazon s3 - Call file after upload

I'm using a php script to upload a file to Amazon S3

$s3->putObjectFile($url,$bucket,$filename, S3::ACL_PRIVATE,array(),array("Content-Type" => "application/json"));

Immediately after the upload, I need to get some information from the file and I call it through Cloudfront but I see that the file is available only after some minutes.

Do you know why and if there is a way to sort this out? Is there a way to have the file immediately available?

Thank you