Solving $T(n)=2T(n-1)$

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I have the following recurrence relation:

$$T(n)=2T(n-1)$$

I would like to find the running time of the algorithm. I tried the following, having in mind that the correct solution is $$O(2^n)$$

So here are my calculations $$2T(n-1) = 4T(n-2) = 8T(n-3) = 16T(n-4)$$ $$... = 2^kT(n-k)$$

As you can see, I observe that each time the number before the T(n-1) is always the 2 to the power of k.

From here I can say that:
Let: $n-k = 0$ $\Rightarrow$ $n = k$.

So: $$2^nT(n-n) = 2^nT(0)$$

And therefore the solution is $$O(2^n)$$ I would like to ask, if the way that I solved the recurrence relation is a valid one and it is proving the recurrence relation is in the class of $2$ to the power of $n$?

CHeers