Don't feed or handle your snake for 10 days. Leave it alone, then the next meal you offer it, just offer it a pinky head. It's really important to leave the snake alone for the next ten days. Try in the meantime to find some really small pinkies.
Your snake may have regurged if you handled it after the first time you fed it. After a hatchling eats, or any snake for that matter, you should leave them undisturbed for two full days. Is you vivarium adequated heated? I mean is there a cool side (75 deg F) and a warm side (85 deg F)? Snakes need a temperature gradient to control body heat, which also aids in digestion.