I changed my own oil the other day but i cant figure out how to reset the oil change timer in the speedometer

 

That is a maintenance interval, not just oil change. So unless you have done all the other work associated with the interval I wouldn't reset it.

However the instructions can be found Here

 

"The only time the following procedure should be performed on a vehicle still under Full Maintenance coverage would be when an owner chose to change their own oil on a SCHEDULED oil service. Doing it at any other time during this coverage will PUSH OUT the next service!

That's from the link above. Looks like you should just let the dealer so this.

 

Simply unplugging your battery will reset your Service Indicator Interval among other things.

 

I don't think to disconnect the battery will reset the service interval indicator.

I did disconnect the battery for multiple times to reset the learning data from the ECU, the service interval remain the same, even the radio preset memory is still there.

 

+1. I have done that for other reasons, but it has never reset the service interval indicator.