I (24m) too stutter since I remember. I finished my degree in international economics and searched for a job for a year in my field (which is transportation and logistics). I went to like 20 different job interviews without success. I was at a similar place as you. I got fed up and just applied for a warehouse job, now 6 months later I am a logistician and couldn't be more happy. This wasn't the job I imagined for myself but I like it. I don't really have to talk and it's so good! No pressured presentations and so on. I think you should look also look elsewhere. I know it ducks because you studied hard for your degree, but who knows? You might like a completely different job just as much.