Many doctors claim that breasts start developing colostrum at around 14 weeks, but some women start leaking before then.
no
Yes.
yes
Yes, it is entirely possible.
because it likes you and thinks you might enjoy its precious breast milk
Breast pads are used by lactating woman because after childbirth breast milk tends to sometimes leak out. These are place in a bra and absorb the breast milk.
In my experience, breasts do not leak until after you have given birth and are actively breastfeeding.
Some women who are breast feeding have leaky breasts. Otherwise it should not leak. Consult a doctor.
Breasts usually leak when the baby cries. It's set up that way. What happens if you choose not to breast feed is that they give you something at the hospital so no more milk will be made. Otherwise it hurts like hell when the milk doesn't get out.
I would suspect that the oil is coming from a broken breast implant. If you do not have an implant (or even if you do) consult your gynecologist.
It might just be hormones but always have these things checked out.