Not sure if you should be concerned but you could plug it in and see if any codes come up. You may have an alternator that is on the way out.
my g37 and my fx50 both do the same thing periodically. sometimes I push the gas when it first starts up, it revs up and then it's fine. It's seldom enough that I haven't put much thought into it, it's been going on for years.when started stalls as soon as it starts. But turns right back on when we start it again. Doesnt matter if the car is cold or warm. This only happens once a couple months.