I am using a SMD Atmega328p, and for making my PCB, I need to know which pins are the analogue pins.
Are they the ADC pins? Or the AIN pins?
Did you check the data sheet?
What do You think of? Analog reading pins or "analog output" pins, PWM?
Of course he did............ Likely used the wrong lenses only.....
No, I didn't think of that. Should have done that first 
ADC is analogue to digital converter, AIN would be analogue input. Where is analogue output in that?
They are the inputs to the analog comparator. Section 23.
ADC1 through ADC8 are ADC inputs. They are multiplexed to one ADC inside the chip. (The Arduino Uno only supports 7 analog inputs.)
There are no true analog outputs, only PWM.
ADC0 through ADC7 on this chip 
Same difference though.
For some reason Arduino chose not to break out pins A6 and A7 on the Uno.
However they are available on the Nano.
@anon57585045
Does this look correct then?
I've got a voltage divider connected to PC0 to measure the battery voltage. That means it would be connected to A0, right?
That part looks okay to me.
That sounds suspicious... 
What other problems do you see??
I just didn't spend the hours looking at it, that I would if it were mine.
Whew. That's a relief. I've spent hours making this - I was really worried for a second there... 
What is the battery voltage?
It's a 18650 battery - should be 3.7v.
It's because they can't be used for general purpose (digital) I/O.
(... and... nobody will ever need more than 640k of memory...) 
The ADC pins. AIN is the analog comparator.
If you're making a PCB, you should probably read the datasheet a bit more carefully...