How come, I (24m) is starting to stutter now when am slightly anxious while I never suffered from this before ?

How come, I (24m) is starting to stutter now when am slightly anxious while I never suffered from this before ? I've never stuttered in my life and was chronically anxious all throughout my teenage years and early adulthood. I overcame most of my anxiety years ago and could function normally without problems. However since these past couple of weeks, I've stuttered a couple of times when under pressure. Which may or may not be related; My sight has also gotten worse/more blurry and I am mumbling more often than before. The only habits that I've changed are cutting off alcohol completely and I've been drinking over 6 redbull cans a day for 3-4 times a week (I know that it's unhealthy and will change this habit now)