Sensitive penile skin can be a cause for premature ejaculation (PE). Though assessment of PE is best done on sexual activity itself. PE also depends on the stimulation of the mind / the excitement level / the gap from last sexual activity.
Always keep multiple modes of stimulation in masturbation
Weight reduction might help.
Next Steps
You should go see a Urologist who will help guide your further
Health Tips
Always maintain good penile hygiene and keep the organ clean with water and soap washing daily.