Thank you all for the advices and sugestions.
My mental tiredness is something hard to deal with...it's not something related to sleepy. It's like if I read one more word my head starts to hurt and I can read more. I guess the only thing that helps when I get on this state is just close my eyes and rest. Maybe this is bigger than it should be...I don't know, I hope not.
The problem is not about what I eat...but there are many days when I wake up tired... Guess I have some sleep problem. Hope is not any other health concern besides mental health issues... My blood analysis are fine, my heart is fine, my brain is fine... Don't make me think about other hipotesis.
Thank you.