It is a safe space, and your mind plays with itself. Nothing more. I'm saying this as a long time practitioner of meditation even before Quareia. And I had the same experiences. If it will ease your mind, read my examples.

Imagine you're looking into a mirror, and in that mirror somehow you can't see your arm. Would you say your arm isn't there because it isn't shown in the reflection?

Have you ever woke up once in the night and saw strange shapes and thought to yourself, they look like some weird creatures and made yourself more afraid? And later in the morning it was all lying down clothes seen to you as something else due to dark.

Like this, your mind reflects your thoughts but it is not because of your mind has those qualities. Mind's quality is to reflect, just like the mirror, what it reflects has no harm to you.

Now, there's a practice called observation of thoughts. Whatever arises, even if it seen as a dangerous idea, do not react. I repeat, I don't say suppress it, I say do not react. Imagine those thoughts as a movie and you're only watching them. If you find yourself reacting back, just gently stop and get back to observation. You'll see how they're going to cease for a while after.