A removed question shouldn’t make you feel bad, you can always edit it. Most of the time you just slipped up or didn’t really explain something as well as you should have in order to expect people to spend time answering your question. If you ever feel a question was removed in error, use the link in the header of the site.
Another common reason for moderators removing questions is that the question is regarding Fluther itself (use the chat room, contact link or read the about!), or is easily answered elsewhere.