I was just reading all over the internet and over the forum, i was wondering,
what do i do if i think of something RANDOM like, “omg gorilla with a hammer”
and then a big ten foot tall Gorilla comes around the corner.
now, im not say im afraid of a monkey with a tool, 
but what do i do if it pops up and it ruins my lucid dream, turing it into a non lucid?
just a thought i did not mean to think of yo u know?
If it turns your lucid dream into a non lucid dream you can’t really do much about it, can you?
sorry i may have worded it wrong,
i mean what if you THINK of somthing scary, and it spawns there, and you dont want it there, sure you have control, but i tend to do that OFFTEN,
so il be thinking of Ghosts and demons left and right
Then you have a screwed up imagination.
well thanks, that mean i should not attempt ld and i should delete my account here eh?
i mean whats up point if il have nightmares every where.
whatever,
thanks a whole lot for your help…
i guess i should not have asked for help,
i thought you all would have been nice
to people in search of it.
daniel, not everything you think comes true in a LD! 
It has to do with expectation too. Anyway, I’ve thought things in LD’s, from intended thoughts to random thoughts, and they stayed only thoughts.
Even if something does appear you can always try to spin and teleport away, or fly or wake up 
I’d say it’s nothing to worry about.
Your could also try taking control of your own thoughts… set firm goals. It actually usually takes a lot of effort to make something really happen in a LD. So random thoughts wouldnt really produce such an occurence.
Then again, if they do, I would be asking myself why they do, and what does it mean? Once you know those answers… then you can do something more concrete about it.
Just remember that it’s your dream, and it’s you who is in control, not the monkey. You are the master of your fellings, so it’s up to you to keep your calm, and it’s indeed possible.
Another good thing about LD is, you can always ask. If you expect there will be an answer, you can ask about anything, maybe not to a DC because they tend to give stupid, generic answers, but rather to your SC / SG / God, whatever works for you, even questioning the wind can work.
Then, if you think of a gorilla with a hammer, and you think you really shouldn’t, you can ask: “Why am i thinking of such random thing when i should be doing more serious/inspiring stuff etc.”, and you will likely get an answer, altough don’t expect it to come always in wordly form.
Having scary lucid dreams is no reason to quit! Take it as an opportunity to face your fears. Practise bravery. Fact is, if you face the monsters, they will usually stop being monsters. I don’t know if there is much you can do about stopping thoughts from coming. Perhaps some strict mental training can control it. But basicaly, stop obsessing about it and try to take the dreams as they come. If something is scary, give it a hug!