this happens to me sometimes as well, along with strange cramps/charley horses, especially in my feet - i also suspect it is malnutrition and dehydration related. while booze provides enough calories to make me gain weight it's not exactly full of nutrients lol. i also am definitely b-vitamin deficient as i have tested as such even when i was not drinking like i have been (i am a vegetarian and it is very common for vegetarians to be b-deficient) and have not been taking my vitamins because VODKA FOR BREAKFAST ugh. (hoping to stop that pronto, even if it means some twitching.)
thirding that seeking advice from a doctor might be good if it continues or is very bothersome.