Overheating and Drain Battery

[Ch227]

Hello. 

I have a sony experia Z3 ultra and i have had it for a year plus now. Problem started today i was just playing music then realized the battery is draining more than usual and also it starts getting hot at the back of my phone even on safe mode. Went to settings to check whats taking up most of my battery and it says screen amd google play services i force stopped the app and reduced brightness still nothing the battery keeps draining slowly in like 20mins 30% gone. I just had it fixed with a technician a month ago and it was working perfectly fine now its back to overheating and battery drainage 

Help! I dont know what i can do. Both stamina mode and extended usage are activated background apps stopped and the problem will not go away 

[talkingdoctor]

I have just recieved a new Z3+ w/ Marshmallow. Charged the battery to 100%. Then started the phone. I do not have a chip for it yet as I have had to purchase a nano cause my previous phone has a micro. I checked the camera, 3 pics, 1 6 sec video. Checked WiFi logged in to my home router, registered and then turned WiFi off. In this time the phone heated up more than I was used to with previous phones.Then I deleted all images, videos and music files that for some unimaginable reason came installed on the phone.It lost 10% in the time I did this, say 40 mins max. Then I turned phone to Airplane mode. In the meantime it has lost a further 2% in 1 hour. While 2% in 1 hr is fine, 10% in 40 mins without syncing mails or connecting to the internet for more than 10-15 mins is alarmingly bad. That would result in 10 hrs with minimal use. Does the 10% have anything to do with no sim card in the phone? How can I diagnose this before I recieve my new sim card. I have 2 weeks to return the phone for a garanteed refund so any help in sorting this in that time frame would be greatly appreciated.