A call unanswered

A short story about a man, and what may have changed if he answered his phone. But does it matter?

It was almost like any other day for Preston Howard. He got up and headed to the bathroom. It's now or never he thought. He brandished his razor and started his grooming process. After the hour of robotic detail he put into his hair and face he jumps into the shower. About the only unusual thing you can say about Preston is he spends an inordinate amount of time maintaining his body, and has a penchant to taking ice cold showers no matter the time of year. Today is the day, you can do it he says to himself again. He put on his work suit and got ready for work. Today was the day Preston Howard would kill himself.
He had thought out the moment every day for 5 years. He had prepared meticulously for this moment, and there would be no stopping him. It's not the Preston had a bad life or that he wasn't successful. Preston just decided that it was all a little too much effort for him, and wouldn't it all be so much easier to stop now.
He'd always wanted to jump. Something about standing near the edge of a 30 story building charged him with pure adrenaline. 6:00pm today and all will stop. Preston was a caring person in his own unique way. He figured that if he was to kill himself it would best be done after all his coworkers had left for the day. He didn't want them to hit extra traffic on the freeway after all.
Oddly, as he jumped into his work he thought not about what he was doing in only a few hours and just the monotony that was his job. Crunching numbers as an IRS employee was nobodies dream job, but for someone like Preston it let his mind go blank, just the way he preferred it.
5:45 and the office was abandoned, all had gone home for the day, none the wiser that there would be a chalk outline brandishing the entrance come tomorrow morning. As he rode up the elevator to the top floor he finally had a sense of triumph for the first time in his life. He owned the game. He knew the outcome. He walked out onto the rooftop feet determined and unwavering in their steps. Looking over the building he thought nothing but elation. More so than he ever felt before. In fact it's really the first true emotion he had ever felt before..Then something strange, no one usually calls him at this time. His cellphone began to buzz. The caller ID was unknown. Preston never answered his phone if he didn't know the caller. So he stepped off and jumped. Plummeting to the ground until an extreme pain took over his body exploding organs and driving his legs into his skull. Then nothing. A voicemail was left on the phone thought to be a prank from some teenagers. It just said "Hi Preston, it's God. I fucked up."

Author's Note

Totally unfinished work, looking to see if the idea has any merit. Also help with what God should say to him would be nice. Maybe help on what emotions my character has. I was going for cold but empathetic. Maybe some ideas on how to get that across. Thanks guys.