Maybe your eyelid is allergic to something and then cause a sudden swelling eyelid in one eye. When your eyes are exposed to allergens such as dust, pollen, mold, ragweed or animal dander, you are easy to get swelling eyelid if your eyes are allergic to them. In this case, your swelling eyelid will go away itself once you stay away from these allergens. But you should go to see a doctor to figure out the allergens so that you can keep away from them in the later life.
According to MayoClinic.com, puffy eyes or swelling eyelid are typically a temporary condition that can be easily alleviated by various home remedies. You may find swelling eyelid after you get up from bed. This is caused by the way you sleep. I hears that lying flat while sleeping allows fluid to collect beneath the eyes. So, when you sheep, you shall elevate your head with a couple of pillows.