Heads-up for anons wondering why a same post, even with a same image, is posted multiple times:
You'll see the "server took too long" error message(s, amount will vary, just keep clicking), and then the "Flood Detected. Post has been discarded" message. When you first see the '"Post has been discarded" message, odds are VERY great that your message has already posted.
Next time you get the "Flood/Discarded" message, just scroll down, and you'll see your post. Has happened multiple times to anon, so can confirm. God Bless.