I had to do a go-around during my initial training on a similar type due to an unstable approach. Was new to the advanced aircraft type and during the missed we started getting new altitudes and headings(instead of the nice easy and briefed LNAV and VNAV button pushes at the appropriate times). The VS is very high and the new altitude is approaching fast, and there are lots of dimly lit buttons on the MCP that require pushing quickly and properly. I knew I would screw that up and am glad that I disengaged the automatics and handflew with a brief two hundred foot altitude deviation which I think was within limits.
Sometimes you just have to realize that you are not good enough to handle this stuff and try something different. Since then, I do try to review various go-around actions once in a while because I know it can easily be screwed up. A quick brief of go-around actions including hand movements can be useful to ensuring the right button bets pushed.
I also found myself forgetting to push TOGA during manual go-arounds in the sim. So I have added that to my go-around call to make it more likely that it wont get missed. Not SOP but it can be said silently. "Go-around" TOGA "Flaps___". Or just say it all in a real life go around.