Convolution of two independent Bernoulli distributions with parameter $p$

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I have a problem with this exercise:

I have to calculate the convolution of two independent Bernoulli distributions, each with parameter $p$ random variables.

Let $X$ and $Y$ be te two random variables:

The definition of convolution is: $f_{x+y=z}=\sum_{i=0}^k f_x(i)f_y(k-i)$

Proceeding with the definition I have $f_{x+y=z}=\sum_{i=0}^1 f_x(i)f_y(1-i)=\\f_x(0)f_y(1)+f_x(1)f_y(0)=2(f_x(0)f_x(1))$

The last equation is because they have the same $p$.

So I have:

$f_{x+y=z}=2(p^0(1-p)^1p(1-p)^0)=2p(1-p)$

Did I make some mistakes or is everything right?