Somebody’s blood is up
Definition 1 of 1
Pro Tip 1/3Emotional Intensity
This phrase suggests a strong emotional response, not just general annoyance or slight anger. 
After his team lost the finals, David's blood was up, and he couldn't calm down.
Pro Tip 2/3Possible Confrontation
It often implies that the person is ready to argue or take action because of their emotional state. 
With her blood up, she was determined to confront the unfair decision.
Pro Tip 3/3Colloquial Use
It's used in informal situations, so it might not be suitable for formal documents or professional settings. 
When Mark's blood is up, he tends to make rash decisions.