It is highly unlikely that you have an urticaria.
Common diseases associated with changes to the skin (not wheals!) and itchiness include atopic eczema or prurigo. One should also consider the possibility of a parasite infestation (fleas, bed bugs, mites). The causes of itchiness without clear visible skin changes are extraordinarily varied: diabetes, renal failure, liver diseases, hypothyroidism, allergies, tumours or blood diseases can all lead to itchiness. In most cases, however, the itchiness can be directly related to excessively dry skin. Regular application of moisturising creams and lotions, particularly following showering and baths, represents an excellent and effective initial treatment.