I now go lucid quite often, but they only last like a few seconds starting with the last two. The first one everything froze like a stuck movie,then I woke up, in the second dream, the second after I started saying the “lucidity x 1000” thing, everything started shaking and I woke up =(
Sorry to hear about the short lucids 
One of the main reasons people wake up from a lucid dream is that they get too excited. If you get too excited you can wake up from the dream. There are two things I can suggest for you so that you can make your LDs longer: -
- If you were excited upon becoming lucid, it is best if you try not to be. If you stay calm then you can make the dream last longer.
- About the ‘lucidity x 1000’ thing…well, once I shouted to increase lucidity, but I woke up. Instead of shouting you should try a different stabilising technique (e.g: Rubbing your hands together or spinning). That might work for you.
If you feel yourself waking up and there isn’t much you can do, then imagine yourself having a false awakening as you “wake up.” This can work, and it catches out the false awakenings that ocassionally happen.
I hope this helped 
Good luck!
Thanks, I had forgotten about the rubbing hands thing. The only thing is, I wasn’t that excited the second time.
I have the same problem
In a few LD’s I didn’t feel excited but saying “stay calm. I’m calm” while rubbing my hands seemed to help!
Stay calm and have no fear. If you fear something will happen it will. Visualize your LD’s lasting a long time during the day and before bed. Also have a plan of what you want to do when you become lucid so you don’t go do something random in the dream and forget you’re lucid or just get sidetracked. In daily life you may know what you want to do if you become lucid, but without hammering it into your brain you might ignore or forget that and be swept up by the excited feelings.
im always calm cuz i meditate
never have this problem