discrete logarithm problem of ecc
The poblem of computing the private key $d$ from the public key $Q$ is indeed referred to as $ECDLP$. It is crucial that you choose the domain parameters so that the $ECDLP$ is intractable. Concerning your choice of $d$ ... it is too small and can thus be computed efficiently. Imagine $d$ not having 7 Bits like in your example but 192-, 384- or even 512 Bits. You wouldn't get very far using your method (or any other currently known and implementable algorithm). 

In order for the $ECDLP$ to be intractable, $d$ must be adequately chosen so that you cannot just brute-force all values for $d$ until you find a $d$ so that $dP = Q$. This is why curves that are considered as secure today use large values for $n$ and $p$ and create a random value $d$ in the range $[1\dots n-1]$.