The engine (or better, the ECU) has no idea you changed the oil. If your "ENGINE/VEHICLE DIAGNOSIS - EOBD" light (to be clear: the yellow one at top-left of the dash, which looks like an engine) is ON, it means you have a problem somewhere. I find it very strange that it went on right after the oil change, I don't see a reason for that to happen... did you touch anything else on the bike?
For the record, the service reminder indicator is in the dash (next to the gear indicator) and it will turn on when the bike is due for an oil change or desmo service.
Good job in getting MelcoDiag, it can read fault codes and reset your service reminder (and do a bunch of other things too). Definitely recommended.