So Kiz and I changed my plugs, seals, rocker cover gaskets and pod filter this weekend!

Started the car, idled fine and started up/run perfectly etc. Put it in reverse, got on the road, no issues at all. Shifted to D and across to tiptronic and put my foot down, acceleration seemed to be okay until I tried shifting into second... Engine just started revving and I was having nothing whatsoever, it was like I was in neutral. Transmission light came on and I just couldn't shift at all in tip. Moved it back into D and it was okay, but it still over-revved when I put my foot down, only worked normally if i used minimal power...
Checked the motor and the only thing we forgot was to plug in the MAF sensor, but I doubt it would cause this to happen...
We don't know what may have caused it to freak out like this, but I'm really worried now...
Trans was working perfectly fine before hand, so I really hope something isn't broken!