Don't be frustrated that early bedtime didn't work the first time. She *did* end up falling asleep sooner than normal, but it wasn't soon enough since she still had about a 10 hour night. It sounds to me that you were right on the cusp of her sleep window. 15 minutes earlier may have done the trick!
Well, if you *do* try 2 naps, you should absolutely limit that AM nap to no more than 15 minutes or it will be your only nap of the day. I think I'd have her stretch until at least 11 am, if you can. Then hopefully you'll get a 2 hour nap out of her, and then a 6 pm bedtime.
This is a tough phase. A lot of kids go thru an OT cycle at this age because of those stupid eye teeth -- they are super painful and even after they're in they tend to cause pain and exhaustion for a couple of weeks.
If she has a 50 minute nap again, I'd do my best to extend nap. Sit with her in the rocker and try to soothe her back to sleep. She may surprise you! And, if you can get even another half hour out of her it will make that early bedtime work a little better.