Thank you for your query,
Yes the hematoma
will subside gradually and nothing to worry.
In a 24 hours time in a day, most of the time newborn will sleep, and they wake up for feeding.
If the child is taking adequate feeds, sucking is good, urine output is good, do not worry about the sleep.
You can show the eye to the Pediatrician
in well baby visit to look for any abnormality.
Hope I have answered your query.