If you think you're stressed then why not ask yourself the question "Do I want to be stressed". You see, a little stress is considered useful and if you're ok with your stress level then perhaps you shouldn't worry too much.
If you answer is "No" then the good news is that everything is in your control. You don't have to be stressed if you don't want to be. You have a choice and before responding to events you can choose a response or behaviour that make everything less stressful.
I am not looking to tell you how. My experience is that there's many sources of information that will tell you what to do and how to do it as long as you wish to find out. For me the most difficult bit was to realise that it is possible and it is up to me, not to the others, not to circumstances, not to uncontrollable events, not to genes, not to education or background but just up to me.
Just a simple question requiring a positive answer - Do I want to be stressed?