It's good that your manager was supportive.

Maybe you can try to develop a new habit that will help you slow your mind down. For example- if you find yourself wanting to say something- maybe check the time to a cute wrist watch or look at a pretty piece of jewelry.

Sometimes you can be so excited about work that you just forget to be political. That happens to me too in the workplace. When I feel like snapping, I have a trusted colleague who I can run a situation by and ask, "I want to say this do you think that I'm going overboard?" That forces me to slow down and realize that I can't tell her anything petty or unprofessional b/c then I'd look bad.