It's because you clicked on something. If you click and watch something but more importantly like it, dislike it, or comment you'll get more of it.
If you want to stop getting specific things the only option you have is to hit the 3 dots and click don't recommend channel or perhaps not interested, but I've never tried that one I just go with don't recommend channel until it clears out all the stuff I don't like but foolishly engaged with.