Her patches are for her, only. Prescription medications are NON transferrable and should NOT be shared (and legally can't be).For her to get that prescription, she needed to be examined and have her medical history reviewed to make sure it was okay for her to use hormonal contraceptives safely. If you have not done that and do not have your own prescription, you have no idea if it's safe for you.
Patches aren't EC and won't work as such. And if you are pregnant, using hormonal contraceptives can cause damage to a fetus.
If your condom was worn for all genital contact and did not slip off, break or tear, you do not have a pregnancy risk.
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Heather Corinna
Editor and Founder, Scarleteen
My epitaph should read: "She worked herself into this ground."
-- Kay Bailey Hutchinson