Most Helpful Girl
Being introverted means that being around people drains you mentally. Being shy means you’re afraid of people.
Most Helpful Guy
There is no difference between genders where shyness & introversion are concerned, emotionally & physiologically speaking.
Being shy simply means you have difficulty approaching others and being approached socially by people you don't know. It's presently easier for women to be shy because the social norms dictate that guys must initiate contact with girls, not the other way around. A shy guy can easily live his whole life without ever knowing a woman, let alone feeling intimacy & love.
Introversion means that social interaction is emotionally & physically draining. It requires you to take personal alone time to "recharge" before you're capable of more social interaction.