Battery on oneplus 13r

Hey, so I just got my oneplus 13r day before yesterday. While setting up I noticed that the device was heating up. A bit too much. Maybe it's because of the initial set up idk. But later, I charged my device to 80% and went to sleep. Overnight the phone drained 10% battery. I used from 70%-20% and got a screen on time of around 4 hours. Again I charged until 80 and got a screen on time of exactly 4 hours. That too using only 4g network/wifi and only whatsapp, instagram (maybe around and hour) google and reddit. Now I charged until 100 and even then within using 10% minutes, around 10% battery is gone. If anyone is using the same device, can you please confirm if it's like this in general or could it be that I got a faulty device? I'm new to oneplus and it's my second android phone so I'm not really sure what to expect.