You are preaching to the choir. If something happens it happnes because God allows it. But that's not Calvinism explained on this Forum. Calvinism is, in fact, reptuted for its denial of the free will. Calvinists not only deny free will, they mock it!
We do not deny free will. We just deny it in the way you mean it. Man is free in that nobody is stopping him. Man is not free in that his will cleaves and is bound by sin.
If you look at the confessions I posted, many talk about how God preordained to PERMIT the fall. It also showed where Adam and Eve WERE completely free to choose both good and evil. The effects of sin were so destructive that now, though he is invited, though the goodness of God is all around, and though NOBODY, not even God, is stopping him - man will NEVER choose God on his own. Again, I can own a slave and take the cuffs off and say you are free to go, but if he insists on staying in chains and never leaves, then he isn't free and it isn't because of me.