Don't worry: it's nothing serious, I just want to admit something in connection to all this.
There have been times where my mind likes to jump back and forth between positive and negative thoughts. While I'm usually a positive and friendly guy, my brain sometimes tends to switch to negative thoughts, some of which have been kind of sad in a way due to how lonely I initially felt before I entered college (even now, they still tend to come back to haunt me in a way). My brain tends to make me question if the life I'm choosing makes sense or not, and it has caused me to feel down at times because of these negative thoughts. Like I said, nothing serious has come of it, but my brain has sometimes given me thoughts I don't want to think of.
congrats, your a normal human being :V
like....literally thats perfectly normal, wrap it up to mood swings emotional hormones, or something rising and falling in optimism or pessimism, its just perfectly normal
life is full of sad and happy moments, and our brain even if we can't choose to remember them all, it still does and ajoints those to feelings, and what its incline to remember in the background is usually emotions as those easily well up our brains and motions and what not with feelings, it justs natural, and everyone been there, i know some who literally end up on the negative side 6 days out of a week, and then theres people who generally run on happiness ones, but everybody switches on how their brian goes to that day, its nothing bad, its just how humans are internally
and really, its something fightable, one of the reason humans are social creatures is sense of community, sense of understanding, and togetherness, what we hold inside we express or disregard to whats being expressed outside to the sense of ongoingness, so if one feels in the down moment just open up to the community, everyones been in that shoes before, and hearing what goes inside wells a lot more good and relief than people think