GAD?

Go and die?...
Get a dog?...
Go away douche-bag?...
... Generalized Anxiety Disorder?
Yea, the 4th one. I strongly believe I suffer from that. Always out of the blue I will start thinking about useless stuff. The past for example. What is the point about dwelling on all the "what ifs" when it is already too late to do anything about it?
Well the past is not the only thing that goes around in my mind. This also happens when something big or small or important or not is about the happen. Usually when something big and important to me. I would start to think about the possible things I could do followed by the negative stuff that could happen on that day =.=
Just because of this bloody disorder, I have experienced some sleepless nights (rarely), lack of sleep 5-6 hours (quite rare) and light sleeping which is waking up every like hour or two (rarely). The most common occurrence is being unable to sleep after an hour of laying on the bed. Its like I feel tired so I go to bed. When I am on the bed my mind starts to go haywire -.-
I'm sure other people also experience something like this some times or most of the time. Any personal suggestions based on experience or not on how to overcome this annoying thing?