In the meantime I have had two other lucid dream experiences, one where I woke up very quickly before I could enjoy it, the other was better. I suddenly knew I must be dreaming, I don't know what exactly triggered this thought. I was standing on some kind of railroad embankment and then it came to me "hey, I'm dreaming". So I though, hell yeah, if I'm dreaming, then I can fly - and I started to lift off slowly and I was flying/hovering in the air. But then, as I became more aware, the dream world suddenly started dissappearing. I could see and feel it dissappearing - because I was now in control of this world, it started disintegrating. Then I woke up of course...
However, it was really fun, just this one minute of it (or however long it was in real time).
I think my suddenly having experiences like that has something to do with my dream-world changing alltogether in the last time. In the past, the most vivid dreams often had a dark color to it, they were always at night, or at least kind of really dark. Also the locations were always recurring places, or at least similar places, often confined spaces like buildings where I would get lost in.
In recent times I was experiencing vivid dreams in new places, with more light, in more open spaces, like on hills with endless meadows and such.
I think this is a good sign and it shows my mind is losing its fear of freedom, or whatever caused my more claustrophic dreams in the past.