Your thougths are very important
Today I woke up with a lot of energy and it seemed to me that would last all the day.
But by for no reason my energy suddenly vanished my feeling and now I am trying to live my day as well as possible. I've read that everything all you think about are thinking is important because it influences constrains your actions. You can bring about yourself new opportunities if you are optimistic. On the other hand, if you think negativily it's probable that nothing good will happens so after losing my feeling of great energy, I convinced myself not to be negative and go ahead with my day!
Your thougths thoughts are very important
Today I wake woke up with a lot energy and it seemed to me that it would last all the day. (or, the whole day)
But by no reason suddenly vanished my feeling for no reason the feeling suddenly vanished and now I am trying to live my day as well as possible. I've read that all what (or everything) you are thinking is important because it constrains your actions. You can bring yourself new opportunities if you are optimistic. On the other hand if you think negativily negatively it's probable that nothing good happens will happen so after losing my feeling of great energy i I convince myself not to be negative and go ahead with my day!
Very good, Marta. Your meaning was clear, but I have changed a few spelling (or typographical) errors.
Any other changes are to make you sound more natural. For example, to say "all the day" is not wrong, but no native speaker would ever phrase it that way.