Many people's posts here have stated that one warning or another has come to their attention once, never to surface again. Hopefully that is the same in your case.
I remember soon after I took delivery of my E90 325i in 2005, the CEL came on one evening. Turned the car off, waited a few mins, turned it on and off I went, like it never happened. CEL never came on again after that.
Best thing was you taking it to the dealer for a check. Now they have it on record.
328i M-Sport, Estoril Blue, Carbon XP 35 Tint, front heated seats, black Dakota, Sports Suspension, Anthracite Headliner, HUD, Pro Nav, Sunroof, hk 600w, Bi-Xenon, 19" 403M wheels, Reversing Camera, DAB+, Xenon, BT Ext Connect. JB4 on Map 2 with Catless DP produces awesome performance in Sport.