Fixed points and Stability (Nonlinear System)

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$$\dot x = -x + x^3$$ $$\dot y = x + y$$ Where $(x,y) \in \mathbb{R^2}$

I found the fixed points to be:

$$(0,0),(0,1),(0,-1),(1,0),(1,1),(1,-1),(-1,0),(-1,1),(-1,-1)$$

The Jacobian Matrix to be:

\begin{bmatrix} -1+3x^2 & 0\\ 1 & 1 \\ \end{bmatrix}

But every point is unstable.

What am i doing wrong? I feel like:

1) I have too many fixed points and

2) My Jacobian matrix is wrong

Thanks.