Unfortunately that is how the notify button works (replies in the topic, not specifically to your post) and it is essentially how the Profile, Notifications works, it just gives a frequency option (see image1).
Personally I don't use this feature anyway, I just use the "Show new replies to your posts." link at the top of the page (image2). That option also is for new pots in a topic that you created or contributed to, not specifically replies to specific posts.