Thanks for writing your query.
It will be helpful if you give more information on :-
1. What was your fiancée doing when he started developing the swelling in his eye?
2. Any exposure to insect prone area when he developed the swelling?
Acute onset of swelling in one eye can be due to injury
or due to some insect bite.
It is good that you have given ice fomentation and Tylenol
. It will help in reducing the swelling.
You should also give him antihistaminic like Cetirizine
It is advisable that you should first get him examined clinically.
I hope this is helpful to you.