Some women do find that symptoms suddenly start up out of the blue but if you look hard enough you may find an answer. I always say to look at what was going on in your life when the symptoms appeared. Very often it could be due to stress, anxiety, working extra hard, getting ill, changing your diet etc. so you may find a clue!
Sensible exercise is important but don't go overboard. The menopause puts tremendous strain on the body generally and if you push yourself too hard the body can go into 'survival mode' and reduce your energy levels! Doing too much exercise could be a contributory factor here so maybe ease off on the more energetic ones for a little while - sometimes doing relaxation can be more beneficial than exercising for the menopause! In the meantime if you are still exercising a lot I would recommend that you add a good protein shake into your diet every day, especially if you are vegetarian, just make sure it is not full of sugar or artificial sweeteners.
Joint pain is a very common symptom in the menopause, as falling oestrogen can affect the hydration of the joints, causing inflammation and pain. You may find Devil's Claw and Arnica Gel helpful. Check your diet too, as caffeine, high salt and sugar foods and processed foods can all irritate the joints further. I have made a short video on joint health in the menopause and what you can do to help yourself so do take a look if you can.