There are several reasons for your eyes becoming smaller than usual. First of all, it may because that you cried the night before, so that the overabundance of water as well as the salinity in the tears will lead to the angioneurotic edema in the eyes, which means that the blood vessels and nerves in the eyes get edema. If in this kind of case, you can just use ice bag to do cold compress on the eyes, and after a while, the eyes will recover gradually. Secondly, it can be drinking too much alcohol that leads to the eyes becoming smaller than usual. It can be alcohol interaction or alcohol allergy. If in this case, you can take some cetirizine and vitamin C to reduce the edema in the eyes, and pay attention not to eat allergic foods such as durian, nor should you eat spicy foods, and you should have light diet. However, in some cases it can be disorder of liver function, and you should go to the doctor's to have a examination. Inadequate sleep and rest can also lead to eye edema. Therefore, getting good and enough sleep and rest is very important.