When i spend time training my voice, i notice my voice is a little higher and a little more female-sounding but either after swallowing or a short period of time my voice goes back down to my normal male voice. Does this happen with anyone else during voice transitioning?

Also, is it necessary to actually be loud when being in falsetto? When I'm in falsetto, I'm prone to having this loud screech and as i did it my downstairs neighbor (i live in an apartment complex) tapped on the ceiling/floor, signaling me to shut up. So will a more quiet falsetto be just as effective?

I would say don#t force it. If it hurts your throat or gives screeching noises, work on the finetuning - it should not sound too horrible and definitely I believe you do not have to do this too loud at all. Better first find the right resonance spot you are looking for and then increase volume

Hey, i havent read in a voice op because still got this botox thats make my sounds like been drinking abit to much wiskey lately
but i can give a link to my pre op vid and can make the post op vid if you want

What I now want to know is there anything I can do to stop my voice from going back down when I'm able to bring it up to the level I can now get it to?

whenever my voice gets tired I start to sound groggy, then I just lower my pitch oh so slightly and it largely goes away

keep working on it, I'm sure you'll get better at it