I don't know whether or not to do it.
This is great
I don't I should do it or I shouldn't.
This should be: I don't know if I should do it or if I shouldn't
or: I don't know if I should do it or not.
I don't know whether or not I take it as a compliment.
This should be: I don't know whether or not I should take it as a complement
I don't know I should take it as a compliment or I shouldn't.
This should be: I don't know if I should take it as a compliment or not.