So tonight I had my first lucid dream, followed by a second one!

In the first lucid dream I woke up in my bedroom, but some things were different than usual. My dreamcatcher was hanging on the ceiling instead of the wall, I had a nightlight next to my bed which I don't have in reality, and there were all these creepy dolls on my closet that I didn't have in real life. So immediately I realised I was dreaming.
At first I thought I was having the same nightmare I've been having for 7 years now, because I'm always lucid in that nightmare. So I tried to wake up by closing my eyes and counting down from 10, but it didn't work. I waited a while for a monster to show up, but nothing of that happened, so I did a reality check: I pushed my fingers against my palm. Strange enough it felt like it feels in real life - warm, sturdy. My fingers didn't went through my palm. But I was convinced I was dreaming because my room looked different than in real life.
So I decided to do an experiment: I wanted the dreamcatcher gone. With loads of effort I finally got it to disappear, and I felt very happy and excited. I thought to myself: "Now that's really proof of the fact that I'm lucid dreaming right now!"
Maybe it was because I was excited, but then I kinda lost control. I tried to close my door mentally, but it didn't work, so I had to stand up and close it with my hands. When I turned around, the dreamcatcher was back. I realised that it was normal that it was hard to control things, since this was my first real lucid dream and it was actually a battle to control the dream. My curtain was open and when I looked outside, I saw this freaky little girl staring at me in the dark. I screamed out of fear and closed my curtain...
I could feel I was falling in a nightmare, so I calmed down and sat on the edge of my bed. I said out loud: "No. This is MY lucid dream and I WILL keep controling what's happening."
And then I woke up.

Only an hour later I had my second lucid dream!
I woke up in my room again and somehow I immediately knew I was dreaming. I did multiple reality checks this time: touch my palm, look at my hand, look at the mirror. But everything was normal again... So I decided that I would make it abnormal, the way it should be. I grew an extra finger and manipulated my mirror reflection by removing body-parts and later completely removing my head.
When I was satisfied with that, I went downstairs. I thought to myself it would be easier to fly when I was on a staircase, so after a few clumsy jumps I started flying... And it worked!
Downstairs my little brother (who was awfully deformed, really strange) kept attacking me, so I sticked him to the wall. After a little conversation with my mother I tried to fly through the closed window. I could actually feel my head bumping against the glass, untill I truly believed I could fly through it and manipulated the glass so it would let me through.
I kept flying outside for a while, but the dream became less sharp and less detailed. I knew I was losing it, so I rubbed my hands a few times in vain. Only moments later the lucid dream became a normal dream.

What I wanna know is WHY my reality checks didn't work. Maybe next time they will work because that's how I decided it in the dream, but I still think it's strange.
And I'm a little bit afraid that I was just dreaming I was lucid - is that even possible? In the first dream I was lucid for sure, but I'm not so certain about the next dream.

Thanks!