You can’t OD and die. You can ingest too much and be uncomfortable. Chew on a peppercorn. I’ve read it helps come down. Have a shower. Turn on something simple on netflix or your favorite tunes. Get in your pjs and get in bed. Walk around outside for 15 minutes.
Basically, get out of thinking about being terrified by shifting to an activity that engages and distracts you.
You will 100% be okay. You won’t die. You may just be uncomfortable for a while.