I had an infection 3 month ago and the doctor told me it had gone .but the eye which was infected is still and has not gonr bak to its normal size?

Eyelid: I am guessing that you had an eyelid infection termed 'stye'. These usually last a short period of time and are either conquered or leave a swelling termed a chalazion which is a type of cyst. If you have symptoms other than a nodule, or the vision is infected, then see an ophthalmologist. Otherwise it probably is benign and you can choose whether to have it removed.