Oh dear I’m even more worried now as I would have breathed lots of it in.
You won't of, even if it turns out to be asbestos you will only have been exposed to the minutest amount. I have in the distant past (30 to 40 years ago) worked with it, sawing and sanding the dam stuff, I have definitely breathed in a fair bit of the stuff, nearly 60 now still cycling 8,000+ mile a year and fitter than most teenagers!
Don't get me wrong, the stuff is very dangerous and there is no safe limit, but the only people I have seen dying of asbestosis was an uncle who was a lagger in the ship yards, and two aunties who worked in an asbestos factory, their exposure was massive every workday for years (horrible way to die) . Seriously I really wouldn't worry about once scrapping a little bit of wall paper off - but then again I wouldn't scrap any more off.