As for the thread titled "Weird things are happening to me", I definitely do not believe you're insane. Sometimes Shaytan tries to scare us from doing good things. He does this to discourage us with the hopes that if he scares us enough we'll abandon doing those good things. He usually "operates" in the form of something called waswasa. These are his whisperings to you throughout the day and not necessarily during a certain part of the day. However, the fact that you can hear these voices as well as see things externally may mean that it's possible you have a jinn harassing you. In this case, I think you should recite Ayat al-Kursi before going to bed each night. This is one of the most powerful ayaat Allah has bestowed upon mankind and it's for our protection. When a Muslim recites this before going to sleep, an angel stands guard by them and watches over them all night. I haven't posted the daleel (proof) on that here but if you want it, I can give it to you. Also make sure your room is clean and that you yourself are always in a state of cleanliness. Remember to always pray to Allah as well.
The twinkling stars thing doesn't seem too out of the ordinary. They do come out at night and they do twinkle lol

. Sometimes maybe a little more than usual but that may just be because the sky may be more clear on some nights than on others.
As for the "I'm losing my memory" thread, rest assured sister, that it happens to ALL OF US. Remember the waswasa I was telling you about just now? Part of that is making you doubt whether you prayed properly or not. If you doubt yourself, then just redo the prayer. Everything you've stated about forgetting, I've experienced myself as well. Just do your utmost best to put everything else out of your mind and focus on Allah alone. Being forgetful isn't something abnormal; it was said that the Prophet Adam a.s. was extremely forgetful and that we inherit our forgetfulness from him (as stated in Ibn Kathir's
Qisas al-Anbiya).
My point? You're not insane sister, you're just human like the rest of us

None of these are things that Allah can't help you with. Just always remember Him and you'll be fine inshAllah.