One way that I use the Amethyst sometimes, which is less pokey, is that I insert the bulbed end and hold it by the curved end as a handle. I then tilt the curved end back (towards the back wall of the vagina) so that the bulbed end is pushed forward, against the g-spot. So I'd suggest trying that.
And maybe try other glass toys. The Love Journey is probably a good toy for a g-spot beginner, since it has a curved shaft instead of a bent one. It is easy to hold the handle and rock it in different ways to see what feels best. And it is a bit bigger and more filling than the Amethyst.