rewrite rule

I have this 2 rules

RewriteRule ^([^/.]+)/([^/.]+)$ /categories.php?secname=$1&catname=$2
RewriteRule ^([^/.]+)$ /categories.php?secname=$1

When i click on link first time it works fine and in url it show
http://agile-web.com/Articles/dedicated_servers

but now when i click on any other link the url becomes
http://agile-web.com/Articles/Articles/Web_Hosting

and I want
http://agile-web.com/Articles/Web_Hosting

each time I click on link, the url keep on increasing like above(means only last word after last '/' is replaced).

Can anyone slove my problem?

Thank you.