Well, yes, eyestrain can just cause droopy eyelids. According to somme researches, some causes can be related with droopy eyelids, including eye strain. And of course, in common, stress can be directly with eye strain. And then eye strain can just tighten your eye skin, and then in a long term, it will just affect your eyelid, leading to droopy eyelids. That can just make you feel annoying and look unattractive. For the treatments, there are some ways you can just have a try. For example, some tea bags can be effective. Also, you can try some sunscreen too. Just remember to have a good rest, avoiding having stressed. That is also important too.