Why do I speak flawlessly when it’s 1 on 1 but if I’m in a group it’s worse?

Why do I speak flawlessly when it’s 1 on 1 but if I’m in a group it’s worse? Went on a date and had a amazing time, i had 0 trouble communicating with her but i struggled so much to order a pizza from little caesars. How come? Any ideas? I seem to get into my head before I even start talking, and on the date I was felt present the whole time 🤔 My stutter was at it’s all time worse a month or so ago bc I stopped smoking weed. The only people I would talk to were my friends when we smoked and when I stopped smoking weed I realized I created a social anxiety since I wouldn’t talk to no one other than the potheads. I would avoid talking and eye contact with people so they wouldn’t realize I was high.