So I changed the oil in my 2005 997s. I drove the back of the car up on ramps and then unscrewed the drain plug and let it drain for about 20 minutes or so. I changed the oil filter as well. Replaced the plug with new washer and then filled it back up with 8.25 L's of Mobile 1 0-W40. I thought better to underfill and add more later. So I drive the car around for a but and then find a nice flat surface to check the oil on but the electronic check says it's ABOVE full !! 

I'm a little worried. Anyone know if there are consequences or am I just worrying too much. My only thought is that I didn't let enough oil drain out (oil wasn't warmed up enough?) or that since the rear of the car was up on ramps all the old oil didn't drain.

 Should I re-do the whole oil change ?

Who's the expert ?