A long time ago I had an experience not with datura, but a close relative - benedryl (both are dissociatives).
Came home after rolling on ecstasy all night and wanted to go to bed. It's not that easy though after taking a bunch of stimulants. So I took a little bit of a lot of benedryl (iirc ~200mg or 8 pills). Ripped my bong for a bit and felt nice and chilled out. About 30 minutes later though, things started to get weird. Was taking a piss and all these really vivid tears started appearing, like someone ripping the movie screen of my vision with intense psychedelic swirls and stuff behind it. These weren't like lsd or mushroom hallucinations, they were far more real and vivid. It wasn't anything overwhelming though, just small little pockets here and there.
I went back to my room, and holy shit, there were thousands of flies pouring out of my blinds. Like this amorphous mass of flies dripping from between the slats. All the other hallucinations were gone. It was just the flies, and I cannot stress enough how real it was. I went up to it and could get in real close and see all their little wings and glittery eyes. I got in bed and now there were hundreds of spiders crawling on my computer chair. I just laid in bed watching in awe of how real it looked. Then huge spiders started crawling on my ceiling, like the ones from jumanji. It was unsettling, but I was oddly sober (mentally) and knew how common reports of insects and dissociatives were. Except for the psychedelic rips, there were no other hallucinations besides the bugs. I don't even have a fear of spiders or bugs, and always assumed that was the underlying cause.