Thank you for your query.
It is not unusual for your son to be cranky following a bout of infection. It shall take some time for him to become normal.
The ringworm lesion has reddish margins which may be slightly raised. They are distinctly different from a bruise
. What you describe as a bruise needs to be assessed. It could have occurred if your son tripped recently. To be on the safer side get it reviewed by your doctor.
I hope I have answered your query to your satisfaction.
Wishing your son an early recovery.