I commented this on u/impressive_craft_330 's post asking, basically, how individual neurotransmitters make a person feel? For example, if just one kind of neurotransmitter was boosted in your brain one morning, how would your feelings and behavior be affected?

I have B.S. in psych, but frankly, I learned 99% of this through personal research as I used to obsess over this stuff way back when.

Also please let me know if you disagree or can add to this but:

Serotonin: if this were suddenly cranked up, you'd experience all sensory input much more intensely. Even if you have perfect vision it's kind of like putting in glasses, but for all senses. It's all "louder" too but not in a bothersome way (probably). You feel a sense of well being, sort of like, "yeah, I'm living life, and life is meant to be lived." You may be more content simply being as opposed to driven. Too much of this and you might feel anxious or panicky. You can feel overstimulated, on edge, confused, or even hallucinate. All of the above can be experienced with psychedelics.

Dopamine: You just feel good. This is your reward system so you quite literally feel very rewarded. It's a very "fuck yeah" feeling. You feel very driven to do things that keep up this reward feeling such as: accomplishing things, learning, sex, etc. You get laser focused. You probably feel more comfortable socializing. You're goal oriented, regardless of whether it is a healthy goal or not, like literally you are probably more likely to get a lot of work done, be down to party for a while, go down a YouTube rabbit hole, lock on to your own thoughts and stay there... It just depends what you're focused on. Dopamine has a weird self-encouraging effect where the more you have it the more you want. This is likely a survival technique since sex, eating and learning release dopamine and as a species we need to keep doing this to survive. But when you have a lot of it, you generally want more. So too much of this can lead to addiction, paranoia, anxiety, stress, and mania. In fact, the main marker for mania is increased dopamine (although it's not proof). Some drugs zero in on this, not gonna say which but it's easy to find out.

Norepinephrine: you want to move/do something. You feel "jacked", energetic. You almost certainly already know what this feels like at least sort of, because it is the classic stimulant feeling, except moat stimulants also increase dopamine. So this will increase your energy more than the other two, especially physically. Too much and you'll really feel like you have to let the energy out somehow, can't sit still. This is, in my opinion, by far the most straightforward of the 3 and doesn't take much explanation to really understand. Too much can just make you feel painfully restless, anxious, and irritable.

GABA: this inhibits brain activity. It makes your brain "turn off." So really, the more you take, the more you black out. It's also relatively straightforward in terms of what the experience is like. If you've blacked out from alcohol, you have experienced very high levels of GABA. If you haven't, just imagine that you're awake but not conscious. You still function and walk around and do things but you won't make much sense and you won't remember any of it. Take too much of this and you'll fall asleep. The benzodiazapine class of anti-anxiety drugs (Xanax, klonopin, atavan etc) zeros in on this mechanism pretty effectively. Kava also increases GABA a lot. Drugs that increase GABA significantly scare the crap out of me.

Edit: if you have follow up questions feel free to ask.