Yes, of course. I discover things changing in my body every time I look again. And whenever I interact with the world, I discover it has changed significantly since I last interacted.

Of course, since I can't observe anything except what I'm observing right now, I could conclude that I'm creating those observations. But I have noticed time and time again that the world largely looks like the same whether I observe it or not. Also, occasionally things that I didn't observe suddenly happen to me, in a way which is consistent only with them having originated outside myself (for example, a ball hits me in the back of the head).

Do you perceive the ball hit your head through direct experience? Or is it mediated through the interpretation of the mind?

This question makes no sense. There is no distinction between and my mind, so experiences of the mind are by definition direct experiences.

Either way, if you're claiming I'm just a figment of your imagination, this conversation really makes very little sense, and of course there is no proof I can bring that would convince you. The existence of a world independent of our own minds is a pre-requisite for any meaningful conversation.

how did you come to believe there is no difference between you and your mind?

could you somehow test this belief?