I share lots of short videos on instagram where I'm playing other composers pieces as well. I was wondering how the copyright for these 15-30 sec long segments work. Anyone knows anything?

In hungary, we can sign a contract about using a short section of a copyrighted piece and we can pay per month as long as the piece of content is available. It's like 1 usd per months for a 30 sec long video.

Now someone told me that in the US it's way more strict. I was wondering what could happen if a composer ever decides that they don't like seeing me posting short videos.

Of course the first thing is to ask, the second is to give credit, but I'm pretty sure that nearly no one registers their short videos so I'm not sure how it should work.

Anyone any experiences?