Oh security guards trying to feel powerful or whatever. Yeah these kind of things really suck; just know the person was being hyper-irrational, and nothing is wrong with you. There's literally no reason you should be thrown out of a bar for a stutter. What kind of stutter do you have more often? Blocks? Prolongations? I mostly have blocks, and I've had some pretty bad ones where people think think I don't even know my own name xD Funny to look back at now, haha!