Do you have any idea yourself as to why you feel ashamed about using lube?
It's pretty great stuff that is almost always in the condom aisle, because so many people use it. I think of it as a pretty standard part of 'stuff-going-in-stuff' sex, that almost always makes such activities better! Indeed condoms often already contain an amount of lube, so many people use lube without even knowing it.
I could suggest scrolling through the ole twitter feed we made (on behalf of lube) a few years ago https://twitter.com/lubelovesu if you want to chuckle and perhaps cringe at some of the terrible jokes we came up with. It might make lube a bit more of an approachable character!
"In between two tall mountains there's a place they call lonesome.
Don't see why they call it lonesome.
I'm never lonesome when I go there." Connie Converse - Talkin' Like You
One is that hark*, so many young people don't use lube because they don't realise it's an option and have uncomfortable sex as a result. So the assumption that most young people won't benefit from using lube is a myth. I don't think you are in as much of a minority as you think.
Secondly there is going to be variation between one person and another as to how slippery their bits get, just as with almost every other body attribute!
So while there might people who are so lubricious that they never consider using lube, there are also a significant proportion who aren't, but power through having uncomfortable sex, and that's not an outcome we want. We don't have control over how much slidy-gunk our glands produce and we aren't personally responsible for that, so we needn't see that as saying ANYTHING about us negative.
Also on a practical note, you could totally buy some online!
(* Forgive me, I did watch some Shakespeare this week)
"In between two tall mountains there's a place they call lonesome.
Don't see why they call it lonesome.
I'm never lonesome when I go there." Connie Converse - Talkin' Like You