Petite Virgins and Cup Insertion Difficulties

I (a teen-aged virgin with a super shallow vagina) have been trying and trying to make this cup thing work. I couldn't manage to get the Softcup in (when I did manage to insert it properly--like an inch of the cup was sticking out.) I used plenty of lube, and tried all sorts of positions from standing, sitting over the toilet, and lying on my bed with a mirror. Has anyone else had this issue? What cup or tricks ended up working for you?

I've been using pantiliners and pads since I started,and tried Gentle Glide slender tampons by Playtex (they were a bit painful, but I managed to insert them.) I know the Softcup instruction manual said that some women in their trial were unable to use the Softcup. Also, the Softcup is much larger than slender gentle glide tampons. Are any of the reusable cups smaller than the Softcup?

TIA!