It's acceptable colloquial usage, typical of many native speakers, generally southern US but widely used for humerous Southern Belle effect.
I'd put a space between the final stop after 'you...' before beginning the next sentence with 'You'. I'd say the upper-case in the second You was optional in this case. If you replace the ... with a hyphen -, then it would have to be'you - you' (all lower case), instead.
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