Has this ever happened to y'all?

Obviously, there was an unclean presence in your house. I wonder if those boys in your dream could be representing siblings, cousins, or friends involved in some type of witchcraft or something. The camera in the dream could be representing any from of electronic, and these boys were engaged in something that cause these demonic forces to appear. You may need to talk to a sibling and his friend or someone to make sure they are not involved in something evil. The alien in your dream represented an unclean spirit. As time goes on, the dream will make more sense to you.

I do not dream of the slender man from video games. The other figure was probably his tentacle arm thingies.

I have had some dam doozies , maybe a bit like that !

Look to your waking Life and ask yourself who do these beings remind you of? They seem fearful to me, so whom do you fear in your real Life? They have shown up in your dream world and seem like they are "out to get you." Once you identify them, or ace them, they lose their power over you. How can you be frightened by ghosts your mind has made up? See what I am saying. Deal with the people whom you are afraid of in your real Life head on, not in your dreams. Then these dreams will cease to upset you, if you have them at all.

It means that your love life is difficult because you have not been able to adapt to the situation. The point is that love is a battle and happens that as soon as you start to show interest for someone (The camera) someone arrives and takes the girl, and for that reason if you have a rival do not give up prove that you are better that he.