Only a week of owning the ML550

and it wouldn't start this morning. No error / low battery message on cluster whatsoever, is it suppose to give me a message? Everything electronic was working in the car except for it to start-up - must have been the low electricity left in the battery.
Anyway, I went ahead and jump started the vehicle

(I was very hesitant to do so, not knowing what was wrong with it.) and it started fine.
Any ideas?

Bad battery? Has anyone experienced anything similar on their ML?
I'm crossing my fingers that it'll start tomorrow morning.