a few, out of curiosity, and two by mistake lol. DXM can sneak up on you when you say "fuck it, im sick" and take a whole sheet or two. I recently had the same happen with diphen a week ago in tea form, some pharmaceutics OTC 18+ shit. I don't find it fun, its mostly accidental. It gets especially funky when you take an ambien or lyrica, lol.
Keep in mind this is coming from someone who adimently believes there is no such thing as a bad trip - having tripped over 40 times now and oldheading several newbies who have freaked the fuck out. You always learn something, it's always a life time experience, and if you can provide some guidance to the most basic level (safe envrnment etc), its not a waste.