Coolant level on S3

[JESSER S3]

Fellows,
I just noticed that the coolant level on my S3 (only 6,000Kms so far in 6 months) was low and just refilled it (took 400ml).
Do you know if this is normal due to weather (I live in a warm place) and driving style? or should I start worrying about something serious?
Thanks in advance!
Jesser.

 

[Caesium]

Open the water bottle and smell the coolant, does it smell of oil or exhaust?

The coolant should not have decreased over time, its sealed in.