In cryptography this horse has been beaten to death. You don’t experiment. You make it secure, even at the cost of inefficiency, for the sole purpose of preventing the slightest chance of anything happening. Please read these before you eventually shoot yourself in the foot:

Cryptography Engineering Has An Intrinsic Duty of Care - Dhole Moments

Schneier on Security

Why Cryptography Is Harder Than It Looks - Schneier on Security

From e-mail to cellular communications, from secure Web access to digital cash, cryptography is an essential part of today’s information syst...