I've had this experience at various times. I can't say it is or isn't testosterone related but I've felt it with very high levels of testosterone present. In any case, I think this is one of the most disturbing feelings I can have personally. I need to feel passion, I need to feel vitally alive, with fire inside.
I think what may be happening here is that your inner self, or spirit or whatever the hell you choose to call it is beckoning you to consider things more thoroughly, to come in from the outside world and have a chat with yourself. I was lucky in some senses of having a very wealthy father who despite being worth many millions was still a rabid workaholic, being in the office by 6 in the morning, even on Easter. He built a world of wonderful toys, endless financial freedom, vacations and luxuries. Yet he gave NOTHING to those around him. He had little contact with family. His friends were social status friends only and people that made money with him. He has it all yet he has nothing that matters. This gave me a critical experience in realizing the importance of the important things first, people, family, friends, love, life, giving, contribution; an experience few are blessed with at a young age.
What is going to give us meaning differs for each and every one of us. However, I can tell you that one of the quickest ways to establish a sense of meaning is to give to others in some significant way, sometimes it's just random acts of kindness. For others it's participating in Habitat For Humanity, or The Christmas Train, or The Basket Brigade, or whatever it is. To know that other's lives are better because you exist, is for me the first and most critical aspect of developing a feeling of meaning and depth in your life. Find a cause you feel passionate about, volunteer what you have, your time, your money, your efforts, your contacts, whatever; then tell no one you do it. Telling no one about it will prevent the ego from stealing the glory from your heart.