C: sticks to routines and prioritizes work
Whenever you feel stressed, your emotional sensitivity increase. You are more tired, get irritated easily, and you’re more likely to develop a coping mechanism of some kind in order to deal with the pressure that your stress roots from. Sometimes, that pressure can cause you to become hard on yourself, and lead you to feeling negative thoughts. What you think sets up your expectations, your expectations set up your beliefs, and your beliefs determine your actions. When you believe something negative about yourself, you set up low expectations thinking that it is all you can do, and your actions become poor. This leads to poor self image.
It could be due to hormonal imbalances, possibly stress related. However, if you're 20 years old and you have not had regular periods, see a gynaecologist or a GP. I'm confident they're able to provide more answers for you.
Medulla oblongata is the part of the brain that controls heart rate and blood pressure
