Lucid Dreams versus dreams about being lucid

Hi dreamers,
hope you can help me to clarify few things related to LD. I used to be a lucid dreamer (with great dream control), then lost that ability and now trying to get back to it. By the way, I fnd this web site VERY useful.
Till the last night I had a number of dreams about being lucid. Since I have that previous experience in LD it was probably just easy for me to dream about it. But I knew it was not a real lucid dreaming. However, last night I had a dream about which I am not sure if it was lucid or not. Although I was very excited during the dream and shortly after awakening -as I was convinced that it was a LD.
My dream: It starts as a regular dream and then I see a mirror and I say let's check if this is a dream or not, as I knew (from this web site) that a mirror can be used as a reality check. At first, I cannot see myself in it, but then I try harder and then I do see my face in the mirror. Then I have that exciting feeling of knowing that I am in a dream. Somehow I know this is just a dream. Then I say 'find a watch there also' and sure I see a watch and check for the numbers and they seem ok (?)- and to me it is another proof that I am in a dream. I know that this sounds contradictory; I shouldn't be able to see myself as I am in that mirror and the numbers in a dream should look strange.... But in my dream I had the proof I needed and I knew that it was a dream. I remember also telling myself 'do not try to control the dream yet -just observe' (again from this site) and then I look around myself -knowing that this is my dream so let's see what is there...and I see some beautifull scenery and I feel I could fly .But I am holding myself back as I do not want to change anything in that wonderful feeling of being aware that I am sightseeing my dream world. And I think:'the only thing that missing is water, some river or something' (I am not trying to control dream, it is just a thought)- but someone tells me:'Look over there!" I turn to that direction and I see a beautifull beach and blue see.
It is a beautiful feeling...cannot describe it... After a while I woke up and I was convinced that it was a lucid dream. Somehow, during the day... I wasn't so sure anymore.
It seems that,in my dreams, I remember a lot of things from this web site, and I am trying to use it in my dreams...
Is there something I could try to do in my next dream to make sure that it is a real lucid dream? Get a duck, or something... would it prove anything?
By the way, a few nights ago I had a dream that I am flying, I just could not get as high as I wanted - but still it was the act of flying... (this one started as a dream about an elevator that is not working properly...so I go: this is a dream so lets fly! however, I wasn't convinced that it was a LD; perhaps because the feeling of awareness didn't last long enough)
Ok. Enough. How to know the difference beetwen dreaming about being lucid and a real lucid dream?
I should know the answer (as I have that previous experience in LD and dream control) but it is not that simple anymore...
Any suggestions?:?

Well, you knew you where dreaming. That's all of the requirements. If you dream about lucid dreaming then your mind is putting some thought into the subject.