Is it my fault?

So my boyfriends super messy. So usually I'll clean his room up a bit before I leave ya know sort things on his dresser and make his bed. Today he received his first paycheck and needed ID to cash it and he now can't find his school ID. He's keeps asking if i moved it during my straightening up but I don't recall touching his ID I remember seeing it though. Now he's angry and taking it out on me , cursing and saying how I should never touch his room ever again when all I did was try to do something nice. Never even moved the ID. Do you honestly think it's my fault? I think it's his for being irresponsible with his crap. I hate how I do something nice for him and it back fires. I don't get it.