how do you know when you have a problem?

because things dont go they way you expected them to go

You may need to add some more detail into this question:)

I guess very generally speaking you know you have a problem when something has got out of control or is not going the way it should have.

I'm guessing because this was asked in Facebook-You may be asking when do you know you have a problem with Facebook addiction or something? If so, Then it's probably when you are spending more time on there then you are spending doing other interests or vital things. Such as using facebook whilst eating and whilst socialising as well as getting much less sleep because you're on Facebook.

I'm sorry because of the rather vague nature of your question I'm not sure if this is the answer you wanted but I hope It helped anyway:)

When you start asking people incomplete questions.