That’s interesting! Shows how language can often be understood easily through context, which is always an important thing to remember.
As has been said, “nest ti + verb” and “verb stem +est ti ending” are two ways of saying the same thing. It’s partly because of dialects.
“Wnest ti + verb” is used far more often in the North of Wales whilst the short form is used far more often in the South (and in literature).
So the “wnest ti” form can be used hardly at all, or almost all the time, depending on where you are - and use by individuals can vary, of course!
So the worst that could happen if you use “wnest ti” all the time is that you might sound like some people from the North of Wales - which a lot of people actually aspire to! 