I am a teen and I have a bump on my pubic area. It has gotten big but I can't feel it. Help?

Be seen. It sounds like you need to be seen by your family doctor or pediatrician.
Can not tell. If could be cyst, sexually transmitted wart, or other growth. See your doctor for diagnosis and probable minor procedure. If you are under 18 you will need parents permission for procedure.
See your physician. You should make an appointment to see your primary care provider or dermatologist so that the lesion can be adequately evaluated.