Hi Pimples occur due to blockage of oil from oil glands in the skin and it occurs under hormonal influence. Certain factors which may aggravate pimples are stress, oil based occlusive cosmetics and food items like milk and other dairy products. Pimples usually leave behind spots and chances of dark spots increase if you fiddle with them. Your skin tone probably getting darker due to sunlight exposure. Please stay away from direct sunlight and use a gel based sunscreen daily. First you need treatment for pimples which reduces chances of getting more marks and few peeling sessions will help both pimples as well as dark spots. Please consult a qualified dermatologist and follow his advise diligently. You can visit below mentioned website to know tips for care of acne prone skin. Take care. Regards Dr Vijay Adhe, Eternis Skin & Hair Clinic, Pune. www.eternisclinic.com