Here is a reminder to breathe Just take some deep breaths and breathe.
Diaphragm breathing is an easy way to check in with your body and stimulate rest and digest versus fight or flight. You may remember back in biology, physiology or any other health science course hearing about the PNS and SNS. The parasympathetic nervous system and the sympathetic nervous system.

The parasympathetic nervous system is the one that occurs at rest, this is the one stimulated by belly breathing (aka diaphragm breathing). It helps calm and restore essential functions of life.
The sympathetic nervous system is upregulated by stress. Take the new mother cow running after you analogy. This is great in this circumstance as you want to be able to get away, or stand ground and fight back - teach her some respect of your space. But in the circumstance of getting another bill in the mail, or something you really wanted to do falling through, or late for work and stuck in traffic. This situation is not ideal to have all those stress hormones coursing through you with nowhere to go. Your body doesn't use them, rather these just build and can lead to health issues.
Therefore, take a breath! Down regulate the stress and move body toward the PNS side of life to help recover.