Accidentally took quite a bit of what I think was speed thinking it was something else

This is a seeking help post not a please judge my actions post, believe me I’m doing enough of that myself

I have a bag of powder that I found at a small festival recently, it was small shards like ketamine which I assumed it was and ground up and took some of at a party. It didn’t nothing perceptible but I thought tasted like k, that’s what I assumed it was.

Tonight on a long train journey I thought I’d try it again, and took quite a big amount, then some more, then some more, finally realising it was a stim and felt quite like speed, though didn’t exactly taste like it

Fast forward now it’s several hours later and I’m fucking buzzing, heart going hard, and I’m desperate to sleep - I finally managed to stop taking speed for exactly this reason, I can’t deal with the sleep deprivation and fallout. I’ve had 5mg valium a couple of hours ago and then another 5 just now, as well as a few drops of weed oil. It doesn’t feel like the diazepam is gunna help - is there anything else I can do to come down and sleep as soon as I can?

Thank you.