something wrong on the storage display after update iOS 8.1.3

i just update my iPhone to the latest iOS 8.3. then i go to iCloud @ the setting section, it only said that i have less than 0 bytes left on my iCloud storage. i know for a fact that i have 13GBs left are free for my iCloud storage. can someone explain to me what is going on? because i have an iPad and i dont wanna update it yet because of the information is wrong.😕