I had a member come to me after another mod instructed him to shoot a gram of test all at once,he woke up the next morning with the whole right side of his face swollen.
So yes ,its possible, did you do an inj the day before?
Probably an allergic reaction, the alcohol that dissolve the ester and the oil can be factors, also can be just a factor we all are borderline allergics when a combination of allergens, stress, change in eating habits can trigger an allergic reaction to one or several things in your surronds..........
For me anything with red colorant+beans and detergent can cause a swollen lip, eye lids........