if your form looks like this :
<form action="whatever.php" method="get">
<input type="text" name="whatever">
<input type="submit" value="Go">
then you are using and HTML form. Period. If not, then I dont know how to help you.
If you're action is set to the same file as the first form, and theres no code telling the process file which form its coming from (like a hidden input) then you will have to point the second form to the correct file to process that info.
If you're not using html forms, then what are you using?