A better photo would help. It does look like overwatering but also the new growth looks like slight nute burn on the edges Sent from my HTC6435LVW using Grasscity Forum mobile app
What type of soil are you using? What nutes have you given it? How often do you water? What type of water do u feed? How old is it? Looks like its over watered, and you used soil with slow release ferts in it.