It doesn't sound like stuttering to me. For one thing, stutterers nearly always repeat the first syllable of the word (like lo-lo-lo-lo-comotive), and they don't make errors in the syllable itself, it is just repeated. It's not that they can't end a word, it's that they can't start it. Sometimes they might also prolong the first sound of a word (llllllocomotive), or not be able to get going at all (all their articulators might be squeezed together but they can't make a sound). Most people have disfluencies at times (repeating a word, syllable, etc.), but to be a stutterer, a certain proportion of your speech must be disfluent (like say, 5%), and stutterers also develop a lot of negative feelings about their stutter, often avoid words they know they will stutter on, and develop secondary behaviors, such as head jerks, eye blinks, jaw jerks, etc., in an attempt to get out of a disfluency.
Here is a classic example of a stutterer (stammerer for the British) talking about his stuttering. Note how his disfluencies very tense, and also the presence of secondary behaviors such as the eye closing and head jerking:
http://www.youtube.com/watch?v=-epHaW8nTJQ
I've never heard of what you are describing exactly, Sora, but what it sounds most like to me is apraxia of speech, which is characterized by "groping movements" by the articulators (lips, tongue, etc.), which can lead to the type of repeating syllables you describe as the person struggles to produce a sound correctly. People with apraxia of speech have difficulty making their articulators go where they want to go, so that they have difficulty forming sounds. Unlike someone with a phonological disorder (for example, someone with a lisp), people with apraxia make irregular speech errors (i.e., there isn't just a single sound or group of sounds they struggle with). They also experience difficulty with vowels as well as consonants, and their speech can be quite unintelligible. Unless you've always had serious difficulty producing clear speech though, I doubt it is apraxia. The mechanism might be similar though- i.e. related to speech coordination.
Here is a video of a kid with apraxia of speech saying the word "brush"- you can see her groping to produce the sounds correctly (not everyone with apraxia is this severe):
http://www.youtube.com/watch?v=Vwbv2X1f ... re=related
Do you have this difficulty with just the occasional word, or is it a frequent feature of your speech? If it's a real problem, you might want to consult a speech pathologist. If not, then I would assume it's a little glitch in your speech coordination that pops up from time to time. I have some words I struggle saying as well, especially if an "r" and an "l" are right next to each other, like in "world" (ironically, given my background in linguistics and speech pathology, "linguist" and "pathologist" are two words I have trouble with). Everyone's speech glitches from time to time- spoonerisms for example. But unless it's frequent (or causes you distress), it's not something you need to worry about or seek treatment for.
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