Re: Nazar?
The logic is same if we get fever or any other disease and we do not go to doctor because of exactly same reasons… Asking for forgiveness from Allah:subhanahu: can be done regardless… That we all have to do…
Thing is that Allah 
has made this world, a world that is refered to as Aalam-e-Asbaab.. Everything has cause and effect.
It is true and part of our faith that nothing happens except with the wish and will of Allah but Allah has made some rules and Quran tells us that Allah does not deviate from His rules (though He has power to do so and if He wants, no one can change that) …
It also reminds me of a hadeeth regarding “Depending on Allah alone” (Tawakkal A’lal-laah) … a famous hadeeth that I am sure all of us have heard some point in life where Prophet:saw2: said A momin should depend on Allah that He will protect his camel after the momin ties the knot of it.
Allah puts burdon on us to test us if we remain thankful and faithful and patient.