Once you hit the second page, set a cookie in your browser indicating that the second page has been visited. In the first page, before doing the redirection always check whether the cookie is not present.
Instructions on setting a cookie:
<script type="text/javascript">
document.cookie="secondpagevisited=43yj0u3jt;path=/"; //execute this line in the head of second page.
</script>
In first page, check for cookie presence:
<script type="text/javascript">
if(document.cookie.indexOf("secondpagevisited=43yj0u3jt")==-1){
/*do redirection here*/
}
</script>
EDIT: Assuming you control only the first page and not the second page, try this:
<script type="text/javascript">
if(document.cookie.indexOf("secondpagevisited=43yj0u3jt")==-1){
document.cookie="secondpagevisited=43yj0u3jt;path=/";
/*do redirection here*/
}
</script>