Self-promotion is permitted, but should be within reason.

There are accounts which submit only their own content, and that frequently. These tend to get marked as spam, the sites blocked, and often the profiles are banned.

If you submit a mix of sources, including occasionally your own, you should be fine.

Blogs don't qualify as "Show HN": https://news.ycombinator.com/showhn.html

(Speaking as an HN reader. I'm not part of YC.)