I have been working out everyday and suddenly fell ill. not flu, just nausea,shakes & weakness for a whole week. why is this? can exercise be bad 4 u?

Exercise not bad: It is not feasible to provide meaningful opinion without examining you and may be doing some tests. However, it is highly unlikely that exercising is the cause of your symptoms. Keep up the exercise. If your symptoms are not getting better, it would be prudent to see a doctor. For good health - Have a diet rich in fresh vegetables, fruits, whole grains, milk and milk products, nuts, beans, legumes, lentils and small amounts of lean meats. Avoid saturated fats. Drink enough water daily, so that your urine is mostly colorless. Exercise at least 150 minutes/week and increase the intensity of exercise gradually. Do not use tobacco, alcohol, weed or street drugs in any form. Practice safe sex, if you have sex.