Hi and welcome to HCM,thank you for your query.
I think this is just contusion
of abdominal wall and ribs. much harder hit is necessary to cause liver injury
so I dont think you should be concerned. Of course,be cautious and watch for any new signs. pain may persist for 7-14 days and just take painkillers and rest. If pain persists you should do rib xray and liver ultrasound
Wish you good health. Regards.