Why is my eyelid drooping suddenly? And what are my options? (Photo)

Your right brow is a little lower than your left.  But your right lid is actually a little more open than the left - and this eye seems to be turning out a little. You should see an oculoplastic surgeon to determine what is going on here.   

It appears that you have either right upper eyelid retraction or left upper eyelid ptosis (droopy). You should get an oculoplastic exam (by oculoplastic specialist) to determine the exact problem and then a solution.

The eyelids are asymmetrical to 2 asymmetrical eyebrows. One eyebrow is much lower than the other which will cause  one eyelid to be more hooded. A unilateral blepharoplasty may help alleviate the look of the eyelids, but the eyebrows will remain the same unless  the eyebrow is repositioned

You have brow ptosis on the right side. Your right eyebrow has dropped lower than the left and this is causing the skin to hood over your right eyelid, partly obscuring it. Question is, why has this happened now, only on one side? Is there a weakness in the frontal branch of your facial nerve on the right side? When you raise your eyebrows, does the right side feel weaker than the left? If so, you will need further investigation for medical conditions that may be responsible for this and get appropriate treatment.If medical conditions have been ruled out, and the problem is purely aesthetic, then your options are some botox to elevate the brow on the right, or possibly, a right-sided brow-lift operation.

Your picture show uneven eye brow position and not the eye lid. Your left eye brow is higher than right side. I would recommend to leave it alone. You can try Botox but it should be done by an experience injector.

From your photograph it appears you have right brow ptosis or sagging of the right eyebrow.  This downward sag of the eyebrow is encroaching upon the upper eyelid and making that side appeared drooping.Small amounts of Botox on the upper outside corner of the right I may help achieve symmetry.  Please consult an expert board certified plastic surgeon who has a lot of experience injecting into this area.