What is this exercise?

My trainer had me use a curl bar to do a combination exercise that ended with me doing an overhead press -- the kind where my wrists are facing away from my body

The thing is, I'm not sure what the starting exercise was. I think it might have been curls, but I'm not sure how I did the coordination to flip my wrists to the opposite direction. I looked for a video of curls to an overhead press, but all of the videos show a reverse grip.

Any idea of what else the starting exercise could be? I want to do this in the gym by myself, but I also don't want to do it wrong. If you have a video link, that would be awesome. Many thanks!