No worries. I thought I had bricked my phone a few times with the 1st gen iPhone. Man, those times were scary. However, jailbreaking has become wayyyyy easier compared to jailbreaking iOS 1
We'll be here to guide you through the way, just don't wait too long and hopefully Apple doesn't send out an update to block the current jailbreak exploit
Lastly, don't do over-the-air updates, always download the ipsw or just let iTunes do its thing.