Welcome! It would be very unusual for you to be in early menopause at 21. However, the hormone changes in menopause that cause night sweats can be similar to plain old hormone changes. As they shift, this can happen. I wouldn't go directly to menopause but to a hormonal shift or imbalance that could be occurring. In my 20's, I had an issue of producing too much estrogen and had all sorts of side effects from that. It regulated. I went on to have kids. And now as I get older . . . I am approaching more of the hormonal issues related to menopause. I would just log what is happening--- weight issues, night sweats or insomnia, period issues, etc. and go see your doctor. They can easily do a blood work up to check your hormone levels. (which can immediately determine if you have perimenopause --- which again, is very doubtful). They can then help guide you through whatever it is your hormones are doing! Let me know if that makes sense and if you make a doctor's appointment.