I had a really hard time with my first salvia trip. I basically became an abstract painting for the duration of my trip. Paralysed and locked into a perception of certain shapes. It was so fast an onset that I never learned how to operate in it like one does during the rising part of a shroom trip. I was having a bunch of perceptions on different levels, seeing, hearing, smelling, or actually feeling all sorts of things, but never both. as in, everything I heard was invisible, everything I saw was silent... Felt like an eternity.
I didn't understand it. I wouldn't call it a bad trip, I just didn't get out of it what i usually do from other substances. I wasn't happy with the first result so I did salvia again 2 nights later and had a trip that showed me where i went wrong with my first trip. remembered what I'd forgotten and gave me time to unfold it all. Or, enough of it to have a working understanding.
Its an incredible experience. Just don't think of it as recreational.

hmmm... it's been awhile since my last salvia expedition... I need to revisit that place soon.

Well, that's my attempt at explaining the unexplainable. Sorry.