I'm in Type-Moon, Attacking Chaldea From the Start

What do you mean Shirou Emiya's rich adoptive father didn't die, and he already took me as his master? What do you mean the head of the Matou Family is Sakura Matou? She keeps calling me big brother. Oh, and Rin Tohsaka? Yeah, you're still the same, a woman on the verge of going crazy. And why does that Sieg call me Master? What do you mean Ritsuka Fujimaru has already been kidnapped and taken to Antarctica? Where the hell am I? Is this still the normal timeline?! And that kid, should I go save him or not? By the way, where exactly is Marisbury?! (grabs hammer)