It couldn't have been. Adam was sinless. Pride is a sin. What you (and others) are saying is that sin entered into man and then he was disobedient. What happened from scripture is that man was disobedient and sin entered the world.
On that "humble" note, I will close with "good luck."
No one said I'm perfect. ;O)
Transgression or sin is one and the same. You sin in your mind before you act.