My mouth corners look slightly droopy when I keep them still, so I'm considering getting Botox, but will my expression look unnatural?

Even when I'm not in a bad mood, the corners of my mouth look slightly down in photos, so sometimes I end up looking unnecessarily stoic.
It’s not like I get asked if I’m actually angry very often, but I find that feeling is especially strong in photos taken by others compared to selfies.
So at first, I just assumed my mouth shape was natural, but I became interested after learning that some people get lip corner Botox.
What I want is not for the corners of my mouth to turn up sharply and my expression to change completely.
I just wish the feeling that I look too down when I have a blank expression could be softened a little bit haha.
How much change can one actually expect from lip corner Botox?
I'm wondering if there are cases where people receive it just enough to look a very slight drop, like me.
My biggest worry is when I laugh lol
I usually like my smile, but I would be a little embarrassed if the shape of my smile changed from usual due to lip corner Botox, or if I felt uncomfortable when eating or talking.
Is it possible to receive a very small amount at first to observe the reaction?
I am also curious if you adjust both sides differently if the height of the corners of the mouth is slightly different on the left and right.
When I look at the frontal photo, it seems like one side is ever so slightly lower, so I plan to mention this during the consultation as well.
Do I not see the effects immediately, but rather feel them naturally after a few days?
For those of you who have had lip corner Botox, has the difference been noticeable enough for people around you to immediately notice?
I don't know about others, but for me, just the right amount is when I'm slightly satisfied when I look at the photos myself, haha.
I would like to hear from those who have received it naturally about whether there was any discomfort when smiling or speaking.