I have two problem feeder girls, one around 300g and one around 400g. Both have only had one meal in the last 3/4 months.
If your husbandry is up and there are no signs of illness you should be fine. I would suggest that you don't handle too much until your snake is eating regularly again. Also, you can always offer a smaller prey item. I offered my 300g female a smaller pup that wasn't to mobile (she scares easily) and she took it after a 3 month fast. You will learn their habits and become more patient with problem feeding, thats ball pythons for yah.
Good luck with feeding.