In agreement with the others. Talk to a health care professional - otherwise some of us on VGC will be worrying and you might miss out on some lively E3 discussions.

Seriously, please talk, or I will have to share some true scary stories with you.

Read this
http://www.ehow.com/how_2362346_interpret-numbness-left-arm.html

Look for a doctor as soon as possible. I dare to say it was likely psychosomatic,or maybe some nerve inflammation, but it could have been a minor infarction. Better safe than sorry, even if you live in the USA and you have to give your arm as payment.

It's harmless. You are too young to be having any serious chest problems.

http://en.wikipedia.org/wiki/Precordial_catch_syndrome

I've had this happen to me before when I was younger, but it doesn't happen anymore. If you're still worried, you are free to go see a doctor. :P

It's probably just you aren't jerking off enough. When's the last time you rubbed one out?

Tonight you dine in hell.

Yeah, you should go as soon as possible. Waiting for the next time is never good.

I get precordial catch syndrome quite regularly - painful, but I don't experience any left arm numbness, so I'm not sure if it's the same thing

Idk, it's possible that the shock from sharp chest pain caused him to believe his arm went numb, but again he can go see a doctor if he wants and get it checked.

Yeah, it hurts a lot. I panicked the first time and thought it was a heart attack lol. In the wiki article, it says PCS can happen from "being inactive" so I guess it is because gamers sit in their rooms all day and don't exercise. =(

Having sharp chest pains now and again is a worthy sacrifice for being able to sit around playing games all day :)