Suddenly Can't Be Heard On My Cell.

I use my Tracfone mostly to call my boyfriend in New Zealand.  We haven't had a problem at all until tonight.  Called him and it rang through fine but he couldn't hear me. I could hear him clearly but he heard nothing from my end.  I tried turning phone off and then turning back on and recalling but the same thing happened. It's too late to call anyone else so I don't know if its the same on another number or not.