I am currently doing 400mg of tren a week, after the second week I started having bad fever specially at night, I don't want to take any medicine for this fever, as it might get worst, do you think it'll be like this my whole cycle?
Are you sure you have a fever or is it just night sweats?
This is a very common side effect of tren use. I would recommend drinking even more water and spreading out your carbs throughout the day. I would not be afraid to get some quick carbs in at night if you wake up feeling like this.