That's the time my little boy roughly wakes up, so tonight he went down at 8, he's just woken at 3:30, fed and now back in his cot. It is normal and they usually don't sleep right through until around 6 months, however I know it can happen earlier as my first baby slept longer at a younger age x
You can try just rocking but there's no problem with feeding her to sleep again if it's quicker. X