What can you do if you took too much caffeine and need to sleep?

Try: Can try warm milk, Chamomile tea or melatonin along w light reading, warm bath or lavender scent. Valerian (Valeriana officinalis), California poppy (Eschscholzia californica), Wild lettuce (Lactuca virosa), Lemon Balm ((Melissa officinalis)), passion flower (Passiflora incarnata), Chamomile (Anthemis nobilis), Hops (Humulus lupulus), Lavender (Lavandula officinalis), St. John's Wort might help.

Nothing, really.: There's no "antidote" for caffeine. You just have to let it work out of your system, which can take some time depending on how much you drank. May just be a pretty sleepless night. In the future, stop drinking caffeinated beverages several hours before you figure you'll want to go to sleep.