I was around your age when I hit a wall with my stutter, very ashamed and avoiding a lot of situations. I’m now 42 and what I have learned is -the only way over it -is through it. I ended up joining a local stuttering group (in New Zealand) and became braver about openly stuttering at social occasions and at work. The more I stuttered, the more accepting I became with myself. It’s never going to go away, but I don’t beat myself up about it so much, there’s no point. I still get anxious over situations, even now. And that’s ok. I feel the feelings and do the thing anyway.