Swollen eyelids: What should I do?

Has anyone here dealt with swollen eyelids before? For about a month now, my eyelids have been puffy, red, and actually quite painful to the touch. I went to see an ophthalmologist, and they assured me my eyes themselves are perfectly healthy, suggesting this might be some kind of internal inflammatory response or systemic issue. Because of that, I’m looking for some insight—if you've gone through something similar, how did you eventually get it sorted out?
Thanks

Honestly, you’re better off just heading back to your primary care physician; let them be the one to point you in the right direction since it could be anything at this point...
But let’s look at the simplest explanation first. If your eye doctor has already given you the all-clear and said your eyes themselves are perfectly healthy, we have to consider the possibility of allergies. It’s that time of year where pollen counts are absolutely skyrocketing, so an allergic reaction is a very real candidate here.
That being said, I really think the smartest first step would be to get some blood work done. Once you have those results in hand, you'll actually have a clear roadmap for what to do next.