I'm twenty. Should i have sex?

I'm about to turn twenty and am still a virgin (im also a guy). I've "hooked up" with a normal amount of girls, around 10, and i've gone as far as third base with some, but Ive always stopped girls before sex. I've had opportunities to, including one recently with one of the most attractive girls ive ever met, but im not sure if i want to do it. Ive been saving for a serious relationship, but havent found the right girl. Is it worth it to keep waiting, will she even care when the time comes, or should i 'seize the day' like this girl is telling me? I feel like im a virgin in a sea of experienced people who see my problem as stupid.