It's 100% natural to feel that way. I think most all of us have felt shame about our stutter. But it's also wrong. Stuttering isn't a decision we make. It's a burden we have to carry. There's no shame in having the strength and perseverance to stand in front of 200 people while your disability is on display. You ought to consider this a matter of pride. I *promise you* that more than one of your peers thought to themselves "There's no way I could present today if I stuttered like that." Congrats on graduating! Take pride in your accomplishment. Don't let your stutter cast shade on a bright moment in your life.