1. Yes it is possable but highly unlikely. If you did get hacked 9 times out of 10 they found a weak spot on your server.
2. Search your logs all of them. For now tho i would recommend uploading a clean copy of all your files over writing the current ones.
3. Yes, but first need to find out what the problem is to figure out what needs to be done to secure it.
I dont see a screenshot?
Server specs (Server OS / Apache / MySQL / PHP / DragonflyCMS):
Joined: Jun 29, 2004