My voice kind of crashes...

I am not able to explain it properly, So I will give an example.

I was giving an Online presentation (I am a student), The presentation just included giving a speech with a PowerPoint presentation, No camera, or anything else. As I was giving the speech/Presentation, several times (3 to 4 times) my voice kind of crashed, like the volume just went to a minimum, like going out of breath or like choking on my own breath.

And the same thing happened when I approached a girl, This was the 2nd time I approached a girl.

Just a guess...is it due to Anxiety? I was Anxious while giving the presentation as well as when I was approaching the chick.

Edit: Thanks for the help, Appreciate it.