When your decision has taken (specially major), put concentration on your decided issue. There were few alternatives while making decision, don't be bother about those, after taking the decision. Always, there are some good and bad things on every issue. When you taken just look on what you have decided about and try to pick the 'good' things from that, don't be upset about the negative issues of it!
You took that! So it's your thing, make it great, that's it!