Can changing breathing styles cause anxiety?

25 M, I've been a mouth breather all my life. a week ago i started nose breathing. I heard there's benefits, however ive had crazy anxiety for the last 3 days, frequent panic attacks. I thought my glasses were the main cause but I was having a pretty tough attack before a shower and once I stepped in it got worse. while showering I started breathing deeply through my nose and it calmed me but I can feel my body tense, like im expecting another one. has any one else dealt with this?