As someone who has just done that to you:
1. Unless the site is exceedingly slow, I usually press preview before finally pressing submit, then ditch my answer if it adds nothing to what has been posted
2. You can get penalised by the site if you post too much too quickly
3 I am sure that some answers get sent into orbit before being posted. On one occasion recently another poster complained of his posts not being shown; when I went back and looked, his where in front of mine, but had not been there the first time I looked.
The problem will allegedly be solved when the new site comes online. I've worked in the computer industry for over 40 years and have heard it all before, many times!!