Look at the cogwheel menu in the corner of forums page:
"My discussions" opens the list of all the discussions you started
The entry with your forum name takes you to your forums profile page. There you'll find another cogwheel menu with options for "your threads" (same as "my discussions") and "your posts" which lists all your posts.
Comments
Oh, I found it in the upper right corner. Now I can't find a way to delete my post...
Look at the cogwheel menu in the corner of forums page:
It's not possible to delete a post. All you can do is edit it to remove the content.
Got it, thanks!
But others may benefit if they have the same question, so it is nice to just leave posts as they are. :)