Crickets can & do bite.......and they will attack the frog if it is lethargic.
I am going to suggest you also try small bits of either earthworms or red wigglers as a food source. I have noticed that some of our froglets are freaked out by all the legs on a cricket sometimes.
Your frog is an Ornate and once it recovers will probably be a good little eater.
Keep us posted on this little one's progress.