A pinky doesn't take as long to digest as a fuzzy or hopper mouse. Pinky mice are not developed and don't have hard bones. Their muscle tissues are weak as well and not quite as dense so you don't have to wait as long before offering food again with a pinky mouse.
I'd say 2 days is long enough if climate is spot on. Night Crawlers act as a stool softener so the frog will have little to no risk of impaction from feeding after a 2 day wait. Now if it were a fuzzy or hopper(mice for adult frogs) you would wait like Lija recommended.2.5" SVL is the correct length your frog should be before offering a pinky mouse.