It is normal for you to have two not the same eyes when you smile. As we know, the two parts in the whole body are not symmetrical. The two eyes are common to be not the same in size. When you smile, you will absolutely have two different sizes in eyes. You should put it into relax and just smile to make your mood good.
Generally speaking, our eyes would be ok when we smile. From what I can see, there is something wrong with your eyelids, which is quite fragile and might be impaired due to some reasons, such as a lack of vitamins and minerals, or physical injuries, sometimes even some neurological problems. So, here my advice for you is to take an eye exam and figure out some remedies to deal with your problem.
Personally, it is normal to have one eyes close more than the other when we smile. If you carefully observe, you can find almost everyone have such similar situation such as Shannen Doherty and And Jennifer Garner. Nevertheless, they still look beautiful. In fact, we all have little asymmetries. Maybe this is caused by the muscles contract.