Does anyone know how to tell difference in fibro fog and depression

I don't know how to describe how I felt last week.  I'm looking for a way to figure out if I was severely depressed or in a fibro fog.  Does anyone know how to tell the difference?  Any input will be appreciated.

I thought fog was confusion, inability to concentrate, and memory lapses. Depression is more a general feeling of uncontentedness, unwellness, and unhappiness.

Myself is right. A difference doesn't really matter. Many people with fibro also have depression. Dealing with a life changing disease often makes people depressed. Seeing a dr and finding the best treatment for your situation is a good first step. It may be situational or not. There's therapy or medication available. Often with depression taking the first step to get help is hard. Our society is still very down on mental illnesses. Good luck.

I sooooooo wish I could put into words how I feel (and felt last week). 

Things that point me in the direction of depression.  I'm still think I'm somewhat depressed.  I don't find joy in things I should.  Lack of interest. Feeling down (although I'm happy to have my mind somewhat back).  I'm no longer wishing / praying I was dead (yea it was that bad).  I still feel like a failure.  Inability to concentrate.

Things that point me in the direction of firomyalgia.  The PAIN and FATIGUE.  Lack of good sleep; even when I get in the hours I wake unrested. 

I don't feel like I was even me.  I still feel a bit disconnected mind from body, but I was so far from reality.  I shouldn't have been driving.  I shouldn't have been left alone or with my son.  I don't ever want to be in that place again.

It's crazy how one can think one way logically but truly believe another.

I work at a hospital.  Last week, two days after I woke up, I saw my neurologist who I've been to ...... I don't know 3-4 times in the last couple of months.  I went up to him and said Hi.  My name is " " and you haven't seen me in a while.  I think he thought I was crazy for a moment.  I just had to try to explain to him that it wasn't me that was in his office all those times.  He started asking me how he had changed my drugs at my last visit.  My medicines had not changed (they have now based on some lab results).  Even just two days after I came out of my stupor I couldn't explain to him the change that had taken place. 

I wish there was some great writer out there who could put this into words for me.