Hans, rather than posting new, or trying to delete, there is an edit button you can use to go back and edit them. The one you did that has two img blocks b4 the addy, go back hit edit, delete one of the img blocks and try again. good luck
Also, if you are already logged on, hit the preview post button and you can see if it worked b4 posting. The url above is not correct. make sure u hit the right one starting with http...