premenopausal

So I am 37 years old, I have 5 kids I'm and engaged to be married. I have to step kids I am very recently active in the gym, And I am starting to have hot flashes at night. I looked it up online and its Pre menopause. Not what I was expecting at 37. Is anyone else going through this? The changes I have noticed are my sex drive has gone completely down almost non existent. I do not have vaginal dryness because I recently got on nuva-ring. I have mood swings from time to time but I've learned to control them because I know where the attitude is coming from. This is completely weird for me because my sex drive used to be overflowing to the point where my fiance thought it was too much for him now I barely have the urge at all. My sister who is 27 has also notice that should her estrogen as gone down. She said that she also has notice vaginal dryness and she's been eating yogurt like crazy to try to help with the vaginal Dryness. I've told her about the nuva ring. We are both considering going to get hormone shots. Has anyone ever had hormone shots before what are the side effects?