The fall on chest on skateboard may cause some tissue injury
and in rare cases fracture
rib which might be causing pain in the chest.
You should at least have the chest x-ray done to rule out any underlying injury after consulting your doctor/emergency.
Though you may take the pain killers like diclofenac
and apply diclofenac gel locally to control the symptoms for the time being till you visit the doctor.
The lung cancer
occur when a person smokes for years and is unlikely just after a year.
You may have the ct chest done as well if you want to rule out any lung cancer or any mass lession in the lung.
Do try to quit smoking
as it only harms and is not a beneficial thing to do.
Have a happy life and health.