It is hard to tell from the photo, because it is not standardized in its view. That said, it does appear that your right lower eyelid is a bit lower than the left. This type of asymmetry is common. Whether it comes up to the level of being called an actual ptosis is a matter of measurement and the time period over which it arose. You should see an opthalmologist. There are sometimes medical reasons for a ptosis that should be investigated.