I went through exactly the same thing at school. This was almost thirty years ago! It does get better though. If you have the opportunity to get speech therapy, it's well worth it. How I overcame my stutter (for the most part), strangely enough was learning how to sing. Something about how singing requires a different part of the brain than speech. Now I'm no virtuoso but it helped retrain my brain to break the blocks and improve my breathing. I got through it and I'm in a good enough spot with it now. You can too.