Why such big changes in my libido?

Hi, I’m contacting you because I’m confused about my libido. I didn’t lose my virginity until I was 18, I stopped having sex when I reached 19. My libido went down, and had no interest in sex at all. I never used to think about it, or want to do it. I’m 27 soon, and I’m not sure why but since I’ve reached my late 20s, I can’t stop thinking about sex!! Nearly everyday, to the point I’m willing to meet men for one night stands. Why could this be please? And thank you!