Do not worry about that has not solution

I once heard someone say "why worry about what we can not fix?". That made me think about the times that I go late from my home to my work or university, and I angry if there is heavy traffic, if the driver goes too slowly or if it takes too long on a bus stop. Has been my fault the delay but the worry nothing good will bring to my life.

Another example: If I am fired from my job and I have big expenses like paying my house, water, electricity, food, education, etc.., I can not do anything to avoid it; I can only seek some employment or other extra money income, but why I'm frustrated or upset if I don't control the time for a company to hire me?

Each concern will bring stress to my body (and more if I can not do anything to control it). According to my knowledge, this is not healthy and it get older me.
It's difficult to control to this, but I must learn to dominate my character and how I react. I don't must let this dominate me.

In these situations it's best to relax, which will lead to think clearly in a solution or a new opportunity to do better in the future.