I'm curious if this code can really get to the else section!!!???
Let me guess. You assign a time variable with date function. And then you assign an another time variable with one minute later. And you check if the new time (which is 1 minute higher then the old one) is bigger then the old time! Can this code get to the else section?
And also you will get a 60th min if the post is at the 59th min! Just read carefully the date function because what you define in ' " ' is the format of the date! Use date("m-d-Y",mktime(blabla)) to define a newer date.
Still this function can't control the time problem. It should get from somewhere the last operation time to be able to check the time interval between the old calling of the file and the new one!
Long story short I think that your code should be something like:
if ( date("h:a:s") - $_GET['oldtime'] < 1 )
echo "please wait a minute";
Just think the logic of your code a little bit too.