This will not affect your original timeline.
And lets take take this hypothetical a step further:
Sceanrio 2:
Say, in the alt-timeline, present-you arrive in the year when past alt-you were 10 years old, your original parents/guardians/caretakers dies for some reason on this timeline, would you care enough about your alternate-self help them? Like take on the role of a parent/guardian in place of their now-dead parents? (Basically, its a roundabout way of asking: How much can you tolerate yourself?)
My answer:
I think I could probably remember enough of myself to understand my alt-self enough to become friends. But if their timeline got fucked up, and their parents die, I’m not sure I can actually deal with this kid who, is me, but not me, like… I would probably get so annoyed at this kid, but also, I’d think about myself when I was 10, when I was this kid, and then feel pity. Idk if I could ever abandon an alt-self, because I’ve already feel abandoned (not literally, but like as in terms of the emotional side of parental love that I never gotten), I wouldn’t wanna see someone who is practically me, also go though the same abandonment.
Idk… Time travel is so weird.
Aha lolol I felt this.
But then again I’m not sure if my younger self would ever understand what’s happening or end up having even more PTSD, then I try to explain alt-timelines and my alt-self just goes into existential crisis at age 11 and obsessed about time travel. (Because I know I end up obsessing with the idea of time travel, even without an alternate-me intervening)