I only get comments from my design in my email. I can’t find them on the site, and dont know how to reply to them. Is this intentional?

Kayce,
The comments you got are actually listed on your design’s profile page. Anytime you see your design’s name appear almost everywhere in the site (including in your profile page) it is also a link to it. There (design profile) you will see the list of comments. The emails you get are just notifications that comments were posted by somebody regarding your design.
Hope this helps.
Thanks
Alex