You just need to wait the full six minutes before you post. Log-ins, sending messages and attempted posts all reset the waiting period and you'll have to wait another 6 minutes.
Thank you!
So i need to wait 6 min between almost everything i do it seems!
That is the case before you get 15 activity.
When you get 15 activity, the time limit should be just 75seconds, and will be further down when you get higher activity.