This is fairly typical. Keep in mind that while you are on the coumadin your risk of bleeding goes up (since it s an anti-clotting medicine). If you fall and have any significant trauma you may develop large bruises. If you hit your head you should be aware of signs if intracranial bleeding to watch for including headache, nausea/vomiting, and changes in mental status. If any of these appear you should be seen immediately.
Advice and opinions given are based on the information provided and must not be considered an official medical recommendation. The limitations of the internet prevent an appropriate evaluation. Always consult your doctor if there is concern.