The eye is not only shut it's swollen and sunken in a bit. Could be a number of things going on there.
The lip sticking out indicates the possibility of a mouthninfection starting...so mlook inside the mouth along there.
The legs are thin so it's indicating that it needs to be eating more.
Vet might be the best option...and be aware that they can crash quickly...so ASAP is the best option.
If you answered the questions we might have more answers.