Trust me bud it's not the end of the world. I remember my first phone interview where I stuttered a little but I still got the phone I just blamed it on bad reception. The 2nd interview of my life was a video call interview and I stuttered so bad like you can think the worst I couldn't even get my name out but I called myself down and started speaking slowly and with full breath each time I spoke and it got better and I did get the job. So calm yourselves take a second and then speak. Hope this helps.