Oh, I've always been hopelessly clumsy. When I was a child, my mother referred to me as Clumsy-Clot and Baby Elephant and it was entirely justified!
Partly, it's probably because I'm left handed which inevitably leads to a certain amount of awkwardness in a right handed world but that's certainly not the entire reason. If something can be dropped, broken or tripped over then I will drop it, break it or trip over it.
I used to worry about it until I realised this only made matters worse. Now, I just shrug, laugh and try not to get close to anything fragile when browsing in shops or visiting friends with precious china on display.