what you're describing does sound like it could be a form of stuttering, especially the blocks and feeling like words get stuck. The ""uhmms"" and ""ehhs"" might be secondary behaviors people develop to try to push through those blocks. Getting an actual evaluation from a speech-language pathologist would really help you understand what's going on and how to work on it. I've heard great things about Better Speech for this kind of thing, they connect you with licensed therapists online so you don't have to deal with waitlists or traveling to appointments. Since you're already trying to improve your speech, having someone who can give you actual strategies and feedback could make a big differnce. Either way, don't let anyone dismiss what you're experiencing. If it's affecting how you communicate, it's worth looking into.