I tried salvia before shrooms... and to me, the feeling of salvia is different from any other drug... it really fucks you up, and alienates your surroundings (objects change colors,shapes, and look like beings) You can also feel a weird sensation some people call "salvia gravity" where it feels like your body is floating is different directions.

When salvia really hit me, i was smoking oil, and pot, so you should be good with weed, ive ever drank while on salvia tho... i havent had it in awhile.