Oh, that must have been frustrating!!! I really don't know what caused that, that's pretty crazy. It COULD have been... tummy upset from something she ate during the day, teething (tho maybe not b/c you tried the pain killers), bad dreams, a bug bite, or who knows. I'm sure it was just a one-off weird alignment-of-the-planets / must-be-a-full-moon thing! (let's hope so, anyway!) You did the right thing, tho, in keeping her in bed and trying to get her back to sleep until a somewhat decent time of day. As far as what to do for bedtime, I would put her to bed as close to her regular bedtime as possible. So, if her regular bedtime is 8pm, then try to aim for 6:30 or 7, depending on how naps go and how she is doing.
Speaking of naps, you mentioned in your email that she's really fussy between her nap and bedtime. How long are her naps? Is she managing to get 2.5-3 hrs? If not, are you putting her to bed early? If she's really fussy, it's probably a sign that she's not getting quite enough naptime sleep.