Granted. From now on, you will be the tallest person in every room, but you will have to duck to get through most doorways. 
Granted, but it always comes off as arrogance
Granted, you are very confident, but that’s only because of your poor memory - your life continues to be a consistent string of repeated failure
Granted. You are now totally confident … and totally incompetent. Enjoy your new career as a consultant or politician.
Granted, all your online usernames change from petertheprettygood to peterthegreat.
Your confidence builds and your decision making and approach to life leads to increasing success in your career and relationships.
You look great, confidence is just beaming out of you. People treat you better, they assume you’re a person who has it all worked out. Nothing feels out of reach, too difficult. You’re trying and excelling at new skills and hobbies, no longer hampered by self doubt. If you think you can do it, you know you can.
As you climb over the rail of the viewing platform, feeling the wind whipping at your hair and tickling tears from the corner of your eyes, you breathe the city in deeply. You can’t wait to feel your muscles stretch across your arms, scooping and bending the gusts to your whim as you soar. You squint to focus on a helicopter landing pad on a hospital roof, some kilometres away. A good landing spot.
People are screaming at you to stop. It’s not worth it. There’s so much to live for?!
You yell across the wind, ‘I know!’ and give them your most charming wink and a smile. You let go of the railing.
Granted. You lose the ability to feel fear. While this does make you far more confident, it also means you don’t hesitate to dive headfirst into incredibly dangerous situations, one of which shortly leads to your untimely death.
Sure, you’re more confident, but nobody has any faith in you, so the only one that believes in you is you.
Sir, this is the monkey’s paw, not my life biography…
You are now Elon Musk