There is no "submit" button (input field) in that form and it cannot send anything.
seannie, you have a serious case of "spaghetti code" which makes things difficult to follow. Good coding practice separates process (php) from display (html) as far as possible. Also, you are using tables for formatting the output, a practice that has gone out of style maybe ten years ago. Instead of tables you should be using CSS and the proper tags like <fieldset>, <legend>, and <label>. For example:
<form enctype="multipart/form-data" action="<?php echo $_SERVER['PHP_SELF']; ?>" method="post">
<label class="form" for="cd">
<input type="text" name="cd" id="cd" value="<?php echo $_POST['cd']; ?>" size="40" maxlength="31">
<label class="form" for="qty">
<input type="text" name="qty" id="qty" value="<?php echo $_POST['qty']; ?>" size="40" maxlength="31">
<input type="submit" name="action" value="Submit form">
<input type="reset" value="Reset form">
Also, html tags need to be properly nested. In a piece of your code I saw <td> tags that were not inside <tr> tags. It's important to write valid html to make it likely that all browsers will render it correctly. Try testing your html code with the http://validator.w3.org/ validator.
My suggestion would be for you to go back to square one and reorganize (clean up) your code.
Also, to better use the sitepoint forum, use the proper tags to display your code: [ php ], [ HTML ], [ CODE ], as the case may be.
By way of anecdote, I still remember my very first "professional" program back in 1960. It was "big" for the time, a box-full of IBM cards. It was "spaghetti code" so complicated that I could not make heads or tails of it when I tried to debug it. I decided to throw the whole thing in the trash, literally. My colleagues thought I had gone mad but it was the best decision I made, I now try to write code as clean as possible to make sure even I understand it.