New usb-c stick from Aliexpress. Is it safe?

Non-tech pro here. I ordered a usb-c stick off Aliexpress. Once I got it, I immediately started moving a bunch of photos and random files that have been in the so-called “junk drawer” that include some government docs from my iCloud storage.

Afterwards, I started to wonder if that was safe. Is it possible that someone could have remove access to what I transferred to the stick? When I first plugged it in, I saw there was only this 28kb info file that I deleted. But what got me thinking it may be dubious was the date on when it was created (Dec 31, 1969 at 7:00pm) and modified (Dec 31, 1979 at 11:00pm) in the info. Any advice would be greatly appreciated. I’m low key panicking and thinking I need to contact credit bureaus, my bank, etc.