For posts you made you can simply select the "Edit" button to alter contents, but an actual removal would require a host.
25 posts are required to post links, and pictures must actually be posted as links referencing a picture on a hosting site (free options are out there).
If you blindly +1 posts you can hit the 25 mark, but can also alter a link's text so it doesn't look like a link, such as Cakewalk[dot]com.
Just checked your profile, and you should be able to post links (you have 59 posts already). You probably tried to insert a picture and got gobbledegook. Post the pic to imgur or such and then insert a reference link into your post.