2006 E53 4.4 V8 with N62 6spd Auto transmission problem

[Seanc333]

Hi all, any help here would be great.
I have recently changed my transmission fluid, that was a bit of a nightmare in itself. I have the bottom fill set up and didn't know this at the time, all the literature I could find showed side fill, anyway I managed to get it filled but it didn't take as much as I was expecting (7litres) took about 4.5litres. I performed the gear shifts allowing oil to be taken up into transmission. Then upon driving, the gears starting slipping and behaving erratic (high revs, holding gears longer than before and general unhappiness; not smooth at all-like before)
I found info on here saying about performing a reset of the EGS Transmission control GS1904 with DISv57, I have DIS and when following the procedure I could not locate said GS1904, only Transmission Control Management- so I performed a reset of this and the car is extremely unhappy now with even wilder erratic gear shifts both up and down.
Anyone have any thoughts as to what damage I have done?
I am to be getting it back up on the ramps tomorrow to check the oil level because I'm a little bit concerned that I may be don't have enough oil in it, but on saying that I have no warnings indicating this.