How will people see my comments on other user’s blogs?

Your comment will only be attached to the original blog posting. It will not leave any trace in your own profile. The only way a third person can see the comment on a blog will be for that person to look at the original blog and its attached comments, not by navigating through your profile. However, links to recent comments also get posted on the right side column, so check that column to see if anyone posted on your blog.