im the same with shooting my off hand (left), you could try my method of 'trigger training'
while you are sat in front of the telly tonight have your marker with you and snap shoot any blond that walks on screen, is a good way to get yourself used to reacting to somone poping out...also gets you used to holding your marker in your off hand....
when i changed my cocker to a blade frame i did my other halfs head in for days just sitting there clicking the trigger till i got used to hitting 8 ball strings without shorting the trigger.
might help you...might not
end of the day the only way you are gonna get good at anything is practice it