I agree with PP. At this age, my little spirited DD, was very sensitive to too much A time. She really couldn't do much more than 45 mins from awake to back to sleep. If I waited too long she would be overtired and just play. She actually still acts like that when I miss her window of sleepiness. Today I got home 30 mins after her nap time and she proceeded to play for an hour in her crib. I also agree with writing down her schedule for a few days to see a pattern. Also, does she sleep in PnP or in her bedroom? I would suggest getting a nap routine set up in the room that she sleeps at night. Make it dark and not too much stimulation. Swaddling at this age can really help with naps and bedtime too. My DD would keep herself awake by swinging her arms around....way too stimulating for her at the time. Let us know how it goes!
Lora