IMHO, deleting stuff you've already published is no more than an illusion
you can truncate your log, restore it to an earlier state, but if the system won't restore the subsequent bits you'd already published from the network, it's no more than fooling you
posting a follow-up withdrawing the earlier post is probably the most realistic achievable scenario, unless you're willing to break into and erase others' memories (be they biological or electronic)
or you can abandon, disown and delete the old log, and start a new one. none of this can undo the accident. it's uncomfortable, no doubt, but misaligning expectations and reality is no more than a source of frustration and disappointment