No, that next choice pill under 17 years will not work for a 20years old because when they produced it they medically see into it that its chemical composition should work just for teenagers below 17 years. so return it immediately and get that allocated for your age group or else you risk being pregnant.

Next when buying over the counter medications of this nature, if the seller or pharmacist dont ask your age, make sure you let them know because all drugs have the same chemical intensities as well as functions to a particular infection or case for different ages of people.